작업은 DOM 프로그램과 유럽 연합 (EU) 커뮤니티 FP7 프레임 워크 프로그램의 보조금 211,684 (BACSIN)를 통해 전략적 환경 연구를위한 스웨덴 재단 (MISTRA)에 의해 지원되었다. 우리는 개념 이야기를 돕는에 대한 X-선 분석과 L. 당나라 촬영에 도움 J. Engstrand 감사합니다.

1. P.의 재배 및 수확 의 putida <ol><li> P.의 식민지에 트립신 간장 국물 100 ㎖ (TSB)를 접종하여 모나스의 putida의 스타터 문화를 준비 의 putida 세포는 트립신 간장 국물 (TSA)로 보충 한천에서 배양. 130 rpm으로 설정 떨고 보드에 30 ° C에서 문화를 유지합니다. </li><li> 7 시간 신선한 TSB-매체에 스타터 문화 동등한에서 주 문화의 최종 부피의 1 / 10로 나누어지는을 전송 한 후. 16 시간 동안 130 rpm으로 흔들어 보드에 30 ° C에서 세포를 유지합니다. </li><li> 성장의 16 시간 후 세포는 실온에서 20 분 1,500 XG에서 세포 배양을 회전시켜 수확. 뜨는을 가만히 따르다 및 펠렛 성장 매체에 등장합니다 염화나트륨 용액에 세포를 다시 일시 중단하여 세포를 씻으십시오. 이 경우 150 mM의 염화나트륨 용액을 사용 하였다. , 세포는 다음 번 원심 분리하고 상층 액을 배합 매체에 세포를 현탁 전에 상층됩니다단계 3.2를 참조하십시오. </li></ol> 2. 다른 종의 재배 <ol><li> 다른 박테리아 종의 프로토콜을 적응 재배 및 수확 과정은 그 종의 요구 사항에 따라 변경해야합니다. 수확 세척 단계 (들) 동안 세포를 처리 할 때 삼투 충격을 방지하기 위해, 솔루션의 삼투압 수확의 성장 매체의 일치해야합니다. </li></ol> 3. 세포의 수립 <ol><li> 각각의 매트릭스 구성 요소를 계량하여 배합 솔루션을 준비하고 물에 용해. 등장 조건을 달성하기 위해, 하나 부형제의 양을 조절하거나 원하는 삼투압에 도달하기 위해 염화나트륨 또는 다른 세포와 호환 용질을 추가합니다. 같은 이당류의 낮은 분자량 물질 양을 쉽게 등장 조건을 도달하기 위하여 조정될 수있다. 고 분자량의이다 중합체와 같은 물질, tonicity 그래서 호환 셀 조정할 수있다류트, 예를 들면 염화나트륨 또는 이당류. 물질의 첨가 차례로 동결 건조 행동과 세포의 생존에 영향을 미칠 수있는 제제의 물리적 속성을 영향을 미칠 것이라고합니다. </li><li> 세척 용액을 (이 경우 염화나트륨)에 가만히 따르다하고 각각의 배합 미디어 세포를 다시 일시 중지합니다. </li><li> 세포가 균일하게 분산되어 있는지 확인합니다. 높은 점도의 공식을 사용하여 혼합 된 반면, 낮은 점도의 공식은, 예를 들면., 저어 줄을 추가하고 혼합 균질가 달성 될 때까지 용기를 흔들어 와류 있습니다. </li><li> 동결 건조기 병에 공식 나눈다. 유리 병은 이전과 동결 건조 중에 제거 물의 양을 계산하기 위해 동결 건조 후 샘플, 빈 무게해야합니다. </li><li> 병이 동결 건조기 안에 봉인 할 경우 병에 고무 마개를 추가 4.3 단계를 참조하십시오. </li><li> 동결 건조 전에 각 제제의 세포를 열거, 6 단계를 참조하십시오. </li> &lt;/ OL&gt; 4. 동결 건조 <ol><li> 동결 건조 조건은 제제의 물리적 특성에 맞게 조정해야합니다. 가장 중요한 매개 변수는이 경우 유리 전이 온도 Tg가이 제제의, 물이 여전히 존재 나타 내기 위해 동결 농축 샘플 전이 &#39;에 표시된다. 동결 농축 제제의 전이 &#39;는 쉽게 시차 주사 열량계 (DSC)를 사용하여 측정 단계 7을 참조하십시오. </li><li> 동결 건조 공정의 매개 변수를 조정하여 시료의 온도는 시료의 Tg를 아래로하고 항상하는 챔버 압력 즉 보조, 배합에 얼음 빠른 승화, 즉 기본 건조하고 잔류 물을 수 있습니다 건조. 샘플 온도는 건조 과정에서 &#39;위 전이의 경우 크게 세포의 생존을 감소시킬 시료의 구조적 붕괴의 큰 위험이 있습니다. </li><li> F 후 건조 제품을 보호하기 위하여reeze 건조 시료의 분위기하여 제어 할 수있다. 가능하면 진공 동결 건조 사이클의 끝에서 해제되기 전에, 동결 건조기에 샘플을 밀봉하십시오. 또는 유리 병을 선호하는 분위기로 가득 할 수 있습니다. 그것은 저장 분위기에서 모든 수분이나 산소 선물로 주변 환경에 샘플을 노출되지 않도록하는 것이 중요하는 것은 세포의 생존에 영향을 미칠 것이다. </li><li> 튜브를 무게. </li></ol> 5. 재수 <ol><li> 탈 및 멸균 물 샘플을 재수. 추가 할 물의 양이 동결 건조 중에 제거하고 빈 유리 병, 동결 건조 전후 샘플 같은 유리 병의 무게로부터 계산되는 금액으로이 동일해야합니다. 소용돌이 샘플은 지금 다시 그 솔루션은 동질 나타날 때까지. </li></ol> 6. 열거 <ol><li> 각 샘플에서 100 μl를 그리는 10 배 연속 희석을합니다. 적분의 희석에서나머지 100 μL는 TSA 플레이트에 도금되어 있습니다. 플레이트는 필요한 온도와 시간에서 배양된다. </li></ol> 7. 냉동 행동 제형의 특성 <ol><li> 소량 걸린다 5 - 10 ㎎, 샘플을 뚜껑 DSC-알루미늄 냄비로 묶습니다. 참고로 빈 냄비를 준비합니다. </li><li> DSC 온도 검사 프로그램을 설정합니다. 냉각이 프로그램은 동결 건조 프로그램의 동결 단계를 모방하도록 설정되어 있습니다. 냉각 반응 속도가 수화 공식의 전이 &#39;에 영향을 미칠 수 있으므로이 수행됩니다. 난방 검사에 잘 일반적으로 조사 제제의 예상 전이 &#39;-100 ° C. 아래의 온도를 가지고 시작하기 전에 </li><li> 40 ° C / 분을 사용하는 - 적절한 가열 속도, 5 일반적으로 가열 속도를 선택합니다. 기록 된 열 흐름 신호는 와트로 표현하고 가열 속도에 의해 영향을받을 것입니다. 높은 가열 속도는 전이 &#39;의 큰 신호를 제공합니다. </li><li> 온도 범위를 설정하는 그래서t는 전이 &#39;와 제제의 녹는 양을 다룹니다. </li></ol> 8. 수화 공식의 표면 장력 측정 <ol><li> 이 실험에 사용 된 실험 장치 표면을 측정하는 뒤 Noüy 방법에 따라합니다. </li><li> 주의 백금 반지 및 측정 용기를 청소합니다. 용기는 아세톤으로 세척하고 보풀이없는 티슈로 닦아하고 무색 화염 내부에서 연소된다. 반지는 무색 불꽃에 붉은 빛납니다. </li><li> 솔루션과 용기를 채우고 표면을 측정하기 전에 해결하자. 평형 상태 만 오랜 시간에 도달 한 후에 솔루션의 경우, 예를 들어 고분자, 여기에 사용되는 간단한 설치 질적 데이터를 제공합니다. </li><li> 높은 점도 2 % 예를 들면 솔루션 (W ​​/ W)와 공식에 대한 HEC 또는 HPMC, 표면 장력이 낮은 농도의 용액에서 측정되어야하고 추정. 이 사실을 활용하여 수행 할 수있는0.5 % 이하의 농도 (w / w)에서의 표면 장력 수준을 꺼 놓습니다. </li></ol> 9. 건조 공법의 X-선 분석 <ol><li> 매트릭스 / 박테리아의 작은 금액을 가지고 샘플 홀더에 그것을로드합니다. </li><li> X-레이 회절에 샘플 홀더를 장착합니다. </li><li> 샘플의 모든 결정 단계 현재를 분석 브루 커에서 EVA 프로그램 패키지를 사용할 수 있습니다. </li></ol> 10. 전자 현미경 <ol><li> 튜브의 매트릭스 / 박테리아 소량 밖으로 가지고 SEM 스텁에 고정합니다. </li><li> 스퍼터 코터 (본 연구에 사용 된 열 VGScientific 폴라 SC7640) 및 AU / 팔라듐 또는 백금의 몇 m로 코트 샘플의 SEM 홀더를 넣습니다. 이 실험에서는 스퍼터링 매개 변수는 : ~ 5 1,900 V, 20mA, 20 초 - 10 nm의 오 / 팔라듐 코팅. 코팅은 영상 획득시 전기 충전을 줄일 수 있습니다. 충전이 지속되고 이미지가 발생하면 그것은 얇은 코팅으로 시작하는 것이 좋습니다되어유물, 샘플을 다시 코팅해야한다. </li><li> SEM 챔버의 SEM 홀더를 넣습니다. 해당 이미지 매개 변수를 선택합니다. 그림 2 (FEI 지층 DB235)에 사용되는 악기에 우리는 5 kV의 가속 전압, spotsize 3, 5 mm와 이차 전자 검출기의 작동 거리를 사용했다. </li><li> 선택적으로, 그 자세한 내용을 공개하는 고분자에 포함 된 박테리아의 단면을 잘라 집중 이온 빔을 사용할 수 있습니다. </li></ol>

<ol>
	<li>Wessman, P., Mahlin, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+matrix+properties+on+the+survival+of+freeze-dried+bacteria.">Impact of matrix properties on the survival of freeze-dried bacteria.</a> J. Sci. Food Agric. 91 (14), 2518-2528 (2011).</li><li>Ablett, S., Izzard, M. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+Scanning+Calorimetric+Study+of+Frozen+Sucrose+and+Glycerol+Solutions.">Differential Scanning Calorimetric Study of Frozen Sucrose and Glycerol Solutions.</a> Journal of the Chemical Society-Faraday Transactions. 88 (6), 789-794 (1992).</li><li>Knopp, S. A., Chongprasert, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relationship+between+type+TMDSC+curve+of+frozen+sucrose+solutions+and+collapse+during+freeze-drying.">The relationship between type TMDSC curve of frozen sucrose solutions and collapse during freeze-drying.</a> Journal of Thermal Analysis and Calorimetry. 54 (2), 659-672 (1998).</li><li>Crowe, J. H., Leslie, S. B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Is+Vitrification+Sufficient+to+Preserve+Liposomes+during+Freeze-Drying.">Is Vitrification Sufficient to Preserve Liposomes during Freeze-Drying.</a> Cryobiology. 31 (4), 355-366 (1994).</li><li>Jain, P., Sen, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+glass-forming+biopreservatives+on+head+group+rotational+dynamics+in+freeze-dried+phospholipid+bilayers:+A+P-31+NMR+study.">Effect of glass-forming biopreservatives on head group rotational dynamics in freeze-dried phospholipid bilayers: A P-31 NMR study.</a> Journal of Chemical Physics. 131 (2), (2009).</li><li>Stock, J. B., Rauch, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Periplasmic+Space+in+Salmonella-Typhimurium+and+Escherichia-Coli.">Periplasmic Space in Salmonella-Typhimurium and Escherichia-Coli.</a> Journal of Biological Chemistry. 252 (21), 7850-7861 (1977).</li><li>Crowe, J. H., Hoekstra, F. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Anhydrobiosis.">Anhydrobiosis.</a> Annual Review of Physiology. 54, 579-599 (1992).</li><li>Leslie, S. B., Israeli, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trehalose+and+Sucrose+Protect+Both+Membranes+and+Proteins+in+Intact+Bacteria+during+Drying.">Trehalose and Sucrose Protect Both Membranes and Proteins in Intact Bacteria during Drying.</a> Applied and Environmental Microbiology. 61 (10), 3592-3597 (1995).</li><li>Nesarikar, V. V., Nassar, M. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+cations+and+anions+on+glass+transition+temperatures+in+excipient+solutions.">Effect of cations and anions on glass transition temperatures in excipient solutions.</a> Pharmaceutical Development and Technology. 12 (3), 259-264 (2007).</li><li>You, Y., Ludescher, R. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+sodium+chloride+on+molecular+mobility+in+amorphous+sucrose+detected+by+phosphorescence+from+the+triplet+probe+erythrosin+B.">The effect of sodium chloride on molecular mobility in amorphous sucrose detected by phosphorescence from the triplet probe erythrosin B.</a> Carbohydr. Res. 343 (2), 350-363 (2008).</li><li>Crowe, J. H., Hoekstra, F. A., Nguyen, K. H. N., Crowe, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Is+vitrification+involved+in+depression+of+the+phase+transition+temperature+in+dry+phospholipids.">Is vitrification involved in depression of the phase transition temperature in dry phospholipids.</a> Biochim. Biophys. Acta Biomembr. 1280, 187-196 (1996).</li></ol>

관심 없음 충돌 선언하지 않습니다.

본 연구의 동기는 동결 건조하는 동안 세포의 생존을 위해 중요 할 수있는 몇 가지 제형의 특성을 조사하는 것이었다. 고유의 건조 내성이 다른 종 사이에 차이가 있지만, 그림 1A, 다른 공식 지원 세포의 생존과 유사합니다 얼마나 잘 추세에 나와 있습니다. 그것은 자당과 Ficoll의 비교로 시작하는 정보입니다. 그것은 세포의 생존을 지원하는 제제의 핵심 요소 따라서는 건조 상태에있...

<table border="1">
	<tbody>
		<tr>
			<td>Name of the reagent</td>
			<td>Company</td>
			<td>Catalogue number</td>
			<td>Comments (optional)</td>
		</tr>
		<tr>
			<td>Ficoll PM 400</td>
			<td>GE-healthcare</td>
			<td>17-0300-10</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>HEC (Natrosol-M Pharm Grade)</td>
			<td>Ashland</td>
			<td>&nbsp;</td>
			<td>Gift from Ashland</td>
		</tr>
		<tr>
			<td>HPMC (Methocel F4M)</td>
			<td>Dow</td>
			<td>&nbsp;</td>
			<td>Gift from the Department of Pharmacy, Uppsala University</td>
		</tr>
		<tr>
			<td>Sucrose</td>
			<td>Sigma-Aldrich</td>
			<td>S2395</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>NaCl</td>
			<td>Sigma-Aldrich</td>
			<td>71376</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Tryptic Soy broth</td>
			<td>Merck</td>
			<td>105459</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Tryptic Soy Agar</td>
			<td>Merck</td>
			<td>105458</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Lyostar II</td>
			<td>FTS Kinetics</td>
			<td>N.A.</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Pyris Diamond DSC</td>
			<td>Perkin-Elmer</td>
			<td>N.A.</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Bruker AXS SMART CCD 1k Diffractometer</td>
			<td>Bruker</td>
			<td>N.A</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Dual-beam FEI Strata DB235 FIB/SEM</td>
			<td>FEI</td>
			<td>N.A</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Kr&uuml;ss Educational Tensiometer</td>
			<td>Kr&uuml;ss</td>
			<td>N.A.</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

formulations for freeze-drying of bacteria and their influence on cell survival

휴대 물을 가역적으로 저장을 촉진하기 위하여 미생물을 불 활성화 제거 할 수 있습니다. 제거 하나의 방법은 부드러운 탈수 방법으로 간주됩니다 동결 건조입니다. 건조하는 동안 세포의 생존을 촉진, 세포는 종종 미리 공식화된다. 제제는 세포를 내장하고 동결 건조하는 동안 세포에 부과되는 각종 유해한 스트레스에서 그들을 보호하는 매트릭스를 형성한다. 우리는 여기에서 동결 건조 후 세포의 생존율을 평가하는 일반적인 방법을 제시하고 우리는 네 가지 공식으로 얻은 결과를 비교하여 보여줍니다 이당류 자당, 폴리머 Ficoll PM400 파생 된 자당, 그리고 각각의 다당류 히드 록시 에틸 셀룰로오스 (HEC 박테리아의 두 가지 변종, P.) 및 히드 록시 프로필 메틸 셀룰로오스 (HPMC) 의 putida KT2440 및 A. chlorophenolicus A6. 이 작품에서 우리는 동결 건조 공법을 준비하는 방법과 mechan를 조사하는 방법을 보여줍니다시차 주사 열량계 (DSC), 표면 장력 측정, X-선 분석과 전자 현미경의 사용과 생존율에 해당 데이터를 관련 제제의 특성에 의해 재수 후 세포 생존의 ISMS. 고분자는 다양한 각도로 각각의 다당류 닮은 자당의 단량체 구조를 얻기 위해 선택되었다. 이 방법 설정을 사용하여 우리는 제제의 특정 물성 1 제어하는 경우 고분자 이당류로 효과적으로 세포의 생존을 지원할 수있는 것으로 나타났다.

표 1은 배합 성분에 대한 자료, 냉동 공법, 건조 시료의 구조와 배합 솔루션의 표면 장력 가열하는 동안 DSC에 의해 기록 된 열 이벤트를 표시합니다. 자당의 T g &#39;는 -40 ° C 2, 3으로 결정되었으며, 20 % w / w 이하 자당 농도에서 감지하기 어려울 수 있습니다. -35에서 열 이벤트는 ° C 아마도 얼음 용해 2의 발병에 관련되어 있습니다. 결정 구조는 HEC와 HPMC ?...

Watch this Scientific Journal Video about Formulations for Freeze-drying of Bacteria and Their Influence on Cell Survival at JoVE.com

Formulations for Freeze-drying of Bacteria and Their Influence on Cell Survival

동결 건조는 종종 실행 가능한 세균 세포의 건조 제품을 얻을 수있는 쉽고 편리한 방법입니다. 프로세스의 문제는 세포의 생존이다. 여기에 우리가 세부 동결 건조하는 동안 세포의 생존을 사용 제형의 특성에 의해 영향을하는 방법을 조사하는 절차입니다.

세포 생존에 박테리아와 그 영향의 동결 건조 공법

Cellular water can be removed to reversibly inactivate microorganisms to facilitate storage. One such method of removal is freeze-drying, which is ...

formulations-for-freeze-drying-bacteria-their-influence-on-cell

Research

JoVE Journal

Biology

23.2K 조회수.  Swedish University of Agricultural Sciences. 동결 건조는 종종 실행 가능한 세균 세포의 건조 제품을 얻을 수있는 쉽고 편리한 방법입니다. 프로세스의 문제는 세포의 생존이다. 여기에 우리가 세부 동결 건조하는 동안 세포의 생존을 사용 제형의 특성에 의해 영향을하는 방법을 조사하는 절차입니다.

비디오: Formulations for Freeze-drying of Bacteria and Their Influence on Cell Survival

Obtaining Hemocytes from the Hawaiian Bobtail Squid Euprymna scolopes and Observing their Adherence to Symbiotic and Non-Symbiotic Bacteria

Studies concerning the role of the immune system in mediating molecular signaling between beneficial bacteria and their hosts have, in recent years, made significant contributions to our understanding of the co-evolution of eukaryotes with their microbiota. The symbiotic association between the Hawaiian bobtail squid, Euprymna scolopes and the bioluminescent bacterium Vibrio fischeri has been utilized as a model system for understanding the effects of beneficial bacteria on animal development. Recent studies have shown that macrophage-like hemocytes, the sole cellular component of the squid host's innate immune system, likely play an important role in mediating the establishment and maintenance of this association. This protocol will demonstrate how to obtain hemocytes from E. scolopes and then use these cells in bacterial binding assays. Adult squid are first anesthetized before hemolymph is collected by syringe from the main cephalic blood vessel. The host hemocytes, contained in the extracted hemolymph, are adhered to chambered glass coverslips and then exposed to green fluorescent protein-labeled symbiotic Vibrio fischeri and non-symbiotic Vibrio harveyi. The hemocytes are counterstained with a fluorescent dye (Cell Tracker Orange, Invitrogen) and then visualized using fluorescent microscopy.

Obtaining Hemocytes from the Hawaiian Bobtail Squid Euprymna scolopes and Observing their Adherence to Symbiotic and Non-Symbiotic Bacteria

This video will demonstrate how to obtain hemocytes (blood cells) from the Hawaiian bobtail squid, Euprymna scolopes for use in cell biological and bacterial adhesion assays. Hemocytes will be stained with a fluorescent dye and exposed to GFP-labeled bacteria.

하와이 밥테일 오징어에서 Hemocytes 구하기 Euprymna scolopes와 공생이 아닌 공생 박테리아들의 준수를 관찰

Studies concerning the role of the immune system in mediating molecular signaling between beneficial bacteria and their hosts have, in recent years, made ...

연구

생물학

Detection of Post-translational Modifications on Native Intact Nucleosomes by ELISA

The genome of eukaryotes exists as chromatin which contains both DNA and proteins. The fundamental unit of chromatin is the nucleosome, which contains 146 base pairs of DNA associated with two each of histones H2A, H2B, H3, and H41. The N-terminal tails of histones are rich in lysine and arginine and are modified post-transcriptionally by acetylation, methylation, and other post-translational modifications (PTMs). The PTM configuration of nucleosomes can affect the transcriptional activity of associated DNA, thus providing a mode of gene regulation that is epigenetic in nature 2,3. We developed a method called nucleosome ELISA (NU-ELISA) to quantitatively determine global PTM signatures of nucleosomes extracted from cells. NU-ELISA is more sensitive and quantitative than western blotting, and is useful to interrogate the epiproteomic state of specific cell types. This video journal article shows detailed procedures to perform NU-ELISA analysis.

Nucleosome ELISA (NU-ELISA) is a sensitive and quantitative method to detect global patterns of post-translational modifications in preparations of native, intact nucleosomes. These modifications include methylations, acetylations, and phosphorylations at specific histone amino acid residues, and hence NU-ELISA provides a global proteomic assay of the overall chromatin modification states of specific cell types.

엘리사에 의해 네이티브 손상 Nucleosomes에 포스트 translational 수정의 감지

The genome of eukaryotes exists as chromatin which contains both DNA and proteins. The fundamental unit of chromatin is the nucleosome, which contains 146 ...

Analyzing the Function of Small GTPases by Microinjection of Plasmids into Polarized Epithelial Cells

Epithelial cells polarize their plasma membrane into biochemically and functionally distinct apical and basolateral domains where the apical domain faces the 'free' surfaces and the basolateral membrane is in contact with the substrate and neighboring cells. Both membrane domains are separated by tight junctions, which form a diffusion barrier. Apical-basolateral polarization can be recapitulated successfully in culture when epithelial cells such as Madin-Darby Canine Kidney (MDCK) cells are seeded at high density on polycarbonate filters and cultured for several days 1 2. Establishment and maintenance of cell polarity is regulated by an array of small GTPases of the Ras superfamily such as RalA, Cdc42, Rab8, Rab10 and Rab13 3 4 5 6 7. Like all GTPases these proteins cycle between an inactive GDP-bound state and an active GTP-bound state. Specific mutations in the nucleotide binding regions interfere with this cycling 8. For example, Rab13T22N is permanently locked in the GDP-form and thus dubbed 'dominant negative', whereas Rab13Q67L can no longer hydrolyze GTP and is thus locked in a 'dominant active' state 7. To analyze their function in cells both dominant negative and dominant active alleles of GTPases are typically expressed at high levels to interfere with the function of the endogenous proteins 9. An elegant way to achieve high levels of overexpression in a short amount of time is to introduce the plasmids encoding the relevant proteins directly into the nuclei of polarized cells grown on filter supports using microinjection technique. This is often combined with the co-injection of reporter plasmids that encode plasma membrane receptors that are specifically sorted to the apical or basolateral domain. A cargo frequently used to analyze cargo sorting to the basolateral domain is a temperature sensitive allele of the vesicular stomatitis virus glycoprotein (VSVGts045) 10. This protein cannot fold properly at 39&deg;C and will thus be retained in the endoplasmic reticulum (ER) while the regulatory protein of interest is assembled in the cytosol. A shift to 31&deg;C will then allow VSVGts045 to fold properly, leave the ER and travel to the plasma membrane 11. This chase is typically performed in the presence of cycloheximide to prevent further protein synthesis leading to cleaner results. Here we describe in detail the procedure of microinjecting plasmids into polarized cells and subsequent incubations including temperature shifts that allow a comprehensive analysis of regulatory proteins involved in basolateral sorting.

This article details the procedures involved in overexpression and analysis of small GTPases in polarized epithelial cells using microinjection technique.

편광 상피 세포에 Plasmids의 Microinjection에 의해 작은 GTPases의 기능을 분석

Epithelial cells polarize their plasma membrane into biochemically and functionally distinct apical and basolateral domains where the apical domain faces ...

Single Cell Transcriptional Profiling of Adult Mouse Cardiomyocytes

While numerous studies have examined gene expression changes from homogenates of heart tissue, this prevents studying the inherent stochastic variation between cells within a tissue. Isolation of pure cardiomyocyte populations through a collagenase perfusion of mouse hearts facilitates the generation of single cell microarrays for whole transcriptome gene expression, or qPCR of specific targets using nanofluidic arrays. We describe here a procedure to examine single cell gene expression profiles of cardiomyocytes isolated from the heart. This paradigm allows for the evaluation of metrics of interest which are not reliant on the mean (for example variance between cells within a tissue) which is not possible when using conventional whole tissue workflows for the evaluation of gene expression (Figure 1). We have achieved robust amplification of the single cell transcriptome yielding micrograms of double stranded cDNA that facilitates the use of microarrays on individual cells. In the procedure we describe the use of NimbleGen arrays which were selected for their ease of use and ability to customize their design. Alternatively, a reverse transcriptase - specific target amplification (RT-STA) reaction, allows for qPCR of hundreds of targets by nanofluidic PCR. Using either of these approaches, it is possible to examine the variability of expression between cells, as well as examining expression profiles of rare cell types from within a tissue. Overall, the single cell gene expression approach allows for the generation of data that can potentially identify idiosyncratic expression profiles that are typically averaged out when examining expression of millions of cells from typical homogenates generated from whole tissues.

Single cell expression profiling allows the detailed gene expression analysis of individual cells. We describe methods for the isolation of cardiomyocytes, and preparing the resulting lysates for either whole transcriptome microarray or qPCR of specific targets.

성인 마우스 Cardiomyocytes의 단세포 Transcriptional 프로파일

While numerous studies have examined gene expression changes from homogenates of heart tissue, this prevents studying the inherent stochastic variation ...

Isolation and Culture of Individual Myofibers and their Satellite Cells from Adult Skeletal Muscle

Muscle regeneration in the adult is performed by resident stem cells called satellite cells. Satellite cells are defined by their position between the basal lamina and the sarcolemma of each myofiber. Current knowledge of their behavior heavily relies on the use of the single myofiber isolation protocol. In 1985, Bischoff described a protocol to isolate single live fibers from the Flexor Digitorum Brevis (FDB) of adult rats with the goal to create an in vitro system in which the physical association between the myofiber and its stem cells is preserved 1. In 1995, Rosenblattmodified the Bischoff protocol such that myofibers are singly picked and handled separately after collagenase digestion instead of being isolated by gravity sedimentation 2, 3. The Rosenblatt or Bischoff protocol has since been adapted to different muscles, age or conditions 3-6. The single myofiber isolation technique is an indispensable tool due its unique advantages. First, in the single myofiber protocol, satellite cells are maintained beneath the basal lamina. This is a unique feature of the protocol as other techniques such as Fluorescence Activated Cell Sorting require chemical and mechanical tissue dissociation 7. Although the myofiber culture system cannot substitute for in vivo studies, it does offer an excellent platform to address relevant biological properties of muscle stem cells. Single myofibers can be cultured in standard plating conditions or in floating conditions. Satellite cells on floating myofibers are subjected to virtually no other influence than the myofiber environment. Substrate stiffness and coating have been shown to influence satellite cells' ability to regenerate muscles 8, 9 so being able to control each of these factors independently allows discrimination between niche-dependent and -independent responses. Different concentrations of serum have also been shown to have an effect on the transition from quiescence to activation. To preserve the quiescence state of its associated satellite cells, fibers should be kept in low serum medium 1-3. This is particularly useful when studying genes involved in the quiescence state. In serum rich medium, satellite cells quickly activate, proliferate, migrate and differentiate, thus mimicking the in vivo regenerative process 1-3. The system can be used to perform a variety of assays such as the testing of chemical inhibitors; ectopic expression of genes by virus delivery; oligonucleotide based gene knock-down or live imaging. This video article describes the protocol currently used in our laboratory to isolate single myofibers from the Extensor Digitorum Longus (EDL) muscle of adult mice (6-8 weeks old).

Isolation and culture of myofibers is the gold standard in vitro system to study the transition of satellite cells through quiescence, activation and differentiation. Importantly, the single myofiber culture system preserves the myofiber/stem cell association, which is an essential component of the muscle stem cell niche.

성인 골격근의 개인 Myofibers 및 위성 세포의 분리와 문화

Muscle  regeneration in the adult is performed by resident stem cells called satellite  cells. Satellite cells are defined by  their position between the ...

Strategies for Tracking Anastasis, A Cell Survival Phenomenon that Reverses Apoptosis

Anastasis (Greek for &#8220;rising to life&#8221;) refers to the recovery of dying cells. Before these cells recover, they have passed through important checkpoints of apoptosis, including mitochondrial fragmentation, release of mitochondrial cytochrome c into the cytosol, activation of caspases, chromatin condensation, DNA damage, nuclear fragmentation, plasma membrane blebbing, cell shrinkage, cell surface exposure of phosphatidylserine, and formation of apoptotic bodies. Anastasis can occur when apoptotic stimuli are removed prior to death, thereby allowing dying cells to reverse apoptosis and potentially other death mechanisms. Therefore, anastasis appears to involve physiological healing processes that could also sustain damaged cells inappropriately. The functions and mechanisms of anastasis are still unclear, hampered in part by the limited tools for detecting past events after the recovery of apparently healthy cells. Strategies to detect anastasis will enable studies of the physiological mechanisms, the hazards of undead cells in disease pathology, and potential therapeutics to modulate anastasis. Here, we describe effective strategies using live cell microscopy and a mammalian caspase biosensor&#160;for identifying and tracking anastasis in mammalian cells.

The term anastasis refers to the phenomenon in which dying cells reverse a cell suicide process at a late stage, repair themselves, and ultimately survive. Here we demonstrate protocols for detecting and tracking cells that undergo anastasis.

추적 아나스타시스, 세포 사멸을 취소 세포 생존 현상에 대한 전략

Anastasis (Greek for &#8220;rising to life&#8221;) refers to the recovery of dying cells. Before these cells recover, they have passed through important ...

A Standardized Method for the Analysis of Liver Sinusoidal Endothelial Cells and Their Fenestrations by Scanning Electron Microscopy

Liver sinusoidal endothelial cells are the gateway to the liver, their transcellular fenestrations allow the unimpeded transfer of small and dissolved substances from the blood into the liver parenchyma for metabolism and processing. Fenestrations are dynamic structures - both their size and/or number can be altered in response to various physiological states, drugs, and disease, making them an important target for modulation. An understanding of how LSEC morphology is influenced by various disease, toxic, and physiological states and how these changes impact on liver function requires accurate measurement of the size and number of fenestrations. In this paper, we describe scanning electron microscopy fixation and processing techniques used in our laboratory to ensure reproducible specimen preparation and accurate interpretation. The methods include perfusion fixation, secondary fixation and dehydration, preparation for the scanning electron microscope and analysis. Finally, we provide a step by step method for standardized image analysis which will benefit all researchers in the field.

The fenestrated liver sinusoidal endothelial cell is a biologically important filter system that is highly influenced by various diseases, toxins, and physiological states. These changes significantly impact on liver function. We describe methods for the standardisation of the measurement of the size and number of fenestrations in these cells.

주사 전자 현미경으로 간 사인 내피 세포의 분석 및 그들의 Fenestrations위한 표준화 된 방법

Liver sinusoidal endothelial cells are the gateway to the liver, their transcellular fenestrations allow the unimpeded transfer of small and dissolved ...

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions

Rotifers are microscopic zooplankton used as models in ecotoxicological and aging studies. Here we provide a protocol for powerful and reproducible measurement of survival time in Brachionus rotifers. Synchronization of culture conditions over several generations is of particular importance because maternal condition affects life history of offspring.

생존 시간의 측정에<em&gt; Brachionus</em&gt; 로티퍼 : 산모 조건의 동기화

Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short ...

Investigating the Detrimental Effects of Low Pressure Plasma Sterilization on the Survival of Bacillus subtilis Spores Using Live Cell Microscopy

Plasma sterilization is a promising alternative to conventional sterilization methods for industrial, clinical, and spaceflight purposes. Low pressure plasma (LPP) discharges contain a broad spectrum of active species, which lead to rapid microbial inactivation. To study the efficiency and mechanisms of sterilization by LPP, we use spores of the test organism Bacillus subtilis because of their extraordinary resistance against conventional sterilization procedures. We describe the production of B. subtilis spore monolayers, the sterilization process by low pressure plasma in a double inductively coupled plasma reactor, the characterization of spore morphology using scanning electron microscopy (SEM), and the analysis of germination and outgrowth of spores by live cell microscopy. A major target of plasma species is genomic material (DNA) and repair of plasma-induced DNA lesions upon spore revival is crucial for survival of the organism. Here, we study the germination capacity of spores and the role of DNA repair during spore germination and outgrowth after treatment with LPP by tracking fluorescently-labelled DNA repair proteins (RecA) with time-resolved confocal fluorescence microscopy. Treated and untreated spore monolayers are activated for germination and visualized with an inverted confocal live cell microscope over time to follow the reaction of individual spores. Our observations reveal that the fraction of germinating and outgrowing spores is dependent on the duration of LPP-treatment reaching a minimum after 120 s. RecA-YFP (yellow fluorescence protein) fluorescence was detected only in few spores and developed in all outgrowing cells with a slight elevation in LPP-treated spores. Moreover, some of the vegetative bacteria derived from LPP-treated spores showed an increase in cytoplasm and tended to lyse. The described methods for analysis of individual spores could be exemplary for the study of other aspects of spore germination and outgrowth.

Investigating the Detrimental Effects of Low Pressure Plasma Sterilization on the Survival of Bacillus subtilis Spores Using Live Cell Microscopy

This protocol illustrates the important consecutive steps required to assess the relevance of monitoring vitality parameter and DNA repair processes in reviving Bacillus subtilis spores after treatment with low pressure plasma by tracking fluorescence-labelled DNA repair proteins via time-resolved confocal microscopy and scanning electron microscopy.

해로운 효과의 낮은 압력 플라즈마 살 균 새 균의 subtilis 포자를 사용 하 여 라이브 셀 현미경의 생존에 조사

Plasma sterilization is a promising alternative to conventional sterilization methods for industrial, clinical, and spaceflight purposes. Low pressure ...

Quantification of Site-specific Protein Lysine Acetylation and Succinylation Stoichiometry Using Data-independent Acquisition Mass Spectrometry

Post-translational modification (PTM) of protein lysine residues by N&#400;-acylation induces structural changes that can dynamically regulate protein functions, for example, by changing enzymatic activity or by mediating interactions. Precise quantification of site-specific protein acylation occupancy, or stoichiometry, is essential for understanding the functional consequences of both global low-level stoichiometry and individual high-level acylation stoichiometry of specific lysine residues. Other groups have reported measurement of lysine acetylation stoichiometry by comparing the ratio of peptide precursor isotopes from endogenous, natural abundance acylation and exogenous, heavy isotope-labeled acylation introduced after quantitative chemical acetylation of proteins using stable isotope-labeled acetic anhydride. This protocol describes an optimized approach featuring several improvements, including: (1) increased chemical acylation efficiency, (2) the ability to measure protein succinylation in addition to acetylation, and (3) improved quantitative accuracy due to reduced interferences using fragment ion quantification from data-independent acquisitions (DIA) instead of precursor ion signal from data-dependent acquisition (DDA). The use of extracted peak areas from fragment ions for quantification also uniquely enables differentiation of site-level acylation stoichiometry from proteolytic peptides containing more than one lysine residue, which is not possible using precursor ion signals for quantification. Data visualization in Skyline, an open source quantitative proteomics environment, allows for convenient data inspection and review. Together, this workflow offers unbiased, precise, and accurate quantification of site-specific lysine acetylation and succinylation occupancy of an entire proteome, which may reveal and prioritize biologically relevant acylation sites.

Here, we present unbiased quantification of site-specific protein acetylation and/or succinylation occupancy (stoichiometry) of an entire proteome through a ratiometric analysis of endogenous modifications to modifications introduced after quantitative chemical acylation using stable isotope-labeled anhydrides. In combination with sensitive data-independent acquisition mass spectrometry, accurate site occupancy measurements are obtained.

사이트별 단백질 Lysine Acetylation 및 Succinylation 산출할 데이터 독립적인 수집 질량 분석을 사용 하 여 정량화

Post-translational modification (PTM) of protein lysine residues by N&#400;-acylation induces structural changes that can dynamically regulate protein ...