rapid-glyco-qualitative-assessment-recombinant-proteins-using-fully

Rapid Glyco-Qualitative Assessment of Recombinant Proteins Using a Fully Automated System

Protein glycosylation, a critical post-translational modification, influences the stability, efficacy, and immunogenicity of recombinant proteins, ...

National Institute of Advanced Industrial Science and Technology

The aim of this study was to determine the physiological role of skin lectins of the Japanese bullhead shark (Heterodontus japonicus). A skin extract was subjected to affinity chromatography using seven different sugars as ligands. Molecular mass and N-terminal amino acid sequence analyses indicated elution of the same protein by each of the seven respective cognate ligands from sugar affinity columns. The predicted amino acid sequence encoded by the cDNA of this protein [designated as H. japonicus C-type-lectin (HjCL)] identified it as a novel fish subgroup VII C-type lectin evolutionarily related to snake venom lectins. HjCL was predicted to bind to mannose because of the presence of a Glu-Pro-Asn (EPN) motif; however, haemagglutination inhibition assays and glycoconjugate microarray analysis demonstrated its binding to numerous structurally diverse sugars. Competitive sugar-binding assays using affinity chromatography indicated that HjCL bound multiple sugars via a common carbohydrate-recognition domain. The mRNA encoding HjCL was specifically detected in the skin, and immunohistochemical analysis detected its expression in uncharacterized large cells in the epidermis. HjCL agglutinated the bacterial pathogen Edwardsiella tarda and promoted immediate clotting of shark blood, indicating that HjCL is involved in host defence on the skin surface especially when the shark is injured and bleeds.

A C-type lectin isolated from the skin of Japanese bullhead shark (Heterodontus japonicus) binds a remarkably broad range of sugars and induces blood coagulation.

Ca/calmodulin-dependent protein kinase I isoforms (CaMKIα, β, γ, and δ) play important roles in Ca signaling in eukaryotic cells by being activated by CaMK kinase (CaMKK) through phosphorylation at a Thr residue in the activation loop. However, we have recently found that, unlike rat CaMKIα (rCaMKIα), C-terminally truncated fragments of zebrafish and mouse CaMKIδ [zCaMKIδ(1-299) and mCaMKIδ(1-297)] produced by Escherichia coli exhibit almost full activity in the absence of CaMKK. To address the CaMKK-independent activation mechanism of CaMKIδ in E. coli cells, here we performed comparative analyses between recombinant zCaMKIδ(1-299) and rCaMKIα(1-294) in vitro. By using a kinase-dead mutant of zCaMKIδ(1-299) and λ phosphatase coexpression method, we elucidated that zCaMKIδ(1-299) was highly autophosphorylated and activated in E. coli during cell culture, but rCaMKIα(1-294) was not. The major autophosphorylation site leading to activation of the kinase was Ser, determined using mass spectrometry analysis in conjunction with site-directed mutagenesis. Furthermore, mimicking phosphorylation at Ser in full-length zCaMKIδ resulted in additional activation of the kinase compared with CaMKI fully activated by CaMKK. Our results provide the first evidence that CaMKIδ is activated through CaMKK-independent phosphorylation at Ser, which might be a clue to understand the physiological regulation of CaMKIδ isoform.

Autoactivation of C-terminally truncated Ca/calmodulin-dependent protein kinase (CaMK) Iδ via CaMK kinase-independent autophosphorylation.

Lectin is a biomolecule that recognizes a specific part of glycans and, thus, has been used widely as a probe for glycoprotein analysis. Owing to the wide repertoire in nature combined with the recent two decades of advances in microarray technology, the multiplexed use of lectins has been widely used for glycan profiling of endogenous proteins. Because protein glycosylation is recognized as being biologically important and is expected to be a reliable disease marker, lectin microarray analysis with highly sensitive detection has been used to discover disease-relevant glycosylation alterations. However, the conventional system is limited to research purposes; thus, its implementation in clinical settings is warranted. Here, we provide an automatic glycan profiling method using GlycoBIST. A unique array format is used for 10-plexed lectin-glycoprotein interaction analysis on 1-mm-sized beads, which are arranged vertically in a capillary-shaped plastic tip. Using a one-boxed autopipetting machine, the whole process (including interaction, washing, and detection) is performed automatically and serially, resulting in reproducible measurements. In this article, a typical method for glycan profiling of a purified glycoprotein and the fabrication of GlycoBIST tips is explained. © 2020 by John Wiley & Sons, Inc. Basic Protocol 1: Fabrication of a GlycoBIST tip Basic Protocol 2: Automatic profiling of a target glycoprotein using GlycoBIST.

Ayaka Ono

Molecular & Cellular Glycoproteomics Research Group,
Cellular and Molecular Biotechnology Research Institute,
Molecular & Cellular Glycoproteomics Research Group, Cellular and Molecular Biotechnology Research Institute

National Institute of Advanced Industrial Science and Technology

Rapid Glyco-Qualitative Assessment of Recombinant Proteins Using a Fully Automated System

Ayaka Ono

Molecular & Cellular Glycoproteomics Research Group,Cellular and Molecular Biotechnology Research Institute,Molecular & Cellular Glycoproteomics Research Group, Cellular and Molecular Biotechnology Research Institute

National Institute of Advanced Industrial Science and Technology

Rapid Glyco-Qualitative Assessment of Recombinant Proteins Using a Fully Automated System

Molecular & Cellular Glycoproteomics Research Group,
Cellular and Molecular Biotechnology Research Institute,
Molecular & Cellular Glycoproteomics Research Group, Cellular and Molecular Biotechnology Research Institute