The present invention relates to the field of protein post-translational modification. More specifically, the present invention provides compositions and methods useful for identifying O-linked glycosylation sites in proteins. In one embodiment, the present invention provides a method for identifying O-linked glycosylation sites of Tn antigen in proteins comprising the steps of (a) digesting proteins present in a sample into peptides; (b) enriching for Tn-glycopeptides; (c) conjugating Tn-glycopeptides to solid phase; (d) labeling Tn using the glycosyltransferse enzyme C1GalT1 and a labeled uridine diphosphate galactose (UDP-Gal) substrate to produce labeled Tn-glycopeptides; (e) releasing the labeled Tn-glycopeptides from the solid-phase using an endopeptidase that cleaves peptides at the N-terminus of O-linked glycans at serine or threonine residues; and (f) mapping O-linked glycosylation sites of Tn antigen using liquid chromatography-mass spectrometry.

The present invention relates to: a composition for an enzymatic conversion reaction for converting proinsulin or a proinsulin analogue into insulin or an insulin analogue, the composition comprises one or more selected from the group consisting of calcium chloride, glycine, and proline, and trypsin and/or carboxypeptidase B; and a method for converting proinsulin or a proinsulin analogue into insulin or an insulin analogue by using the composition. The present invention increases the structural stability of an insulin protein and the stability of the enzyme at the same time so as to significantly improve the enzymatic conversion yield and the purity of insulin, thereby being useful in insulin production processes.

The present invention relates to the novel trypsin ZT isoforms. In particular, the invention relates to the use of trypsin ZT isoforms in medical devices, pharmaceuticals and cosmetics.

Disclosed are compositions and formulations comprising enzymes or other biocatalyst that cleave surface-accessible DNA polymers and/or glycoprotein carbohydrate chains at galactose residues in dental calculus, and optionally further include one or more proteolytic enzymes, thereby destroying the structural integrity of the calculus, and allowing it to be readily removed without requiring special treatment by a trained dental professional. Also disclosed are methods for removing dental calculus using the disclosed compositions and formulations.

The invention discloses a pretreatment method, a preservation method, an automatic treatment system and a detection method for a urine sample, and directs to the technical field of biological detection. The pretreatment method comprises subjecting a urine sample after protein lysis to a reductive alkylation treatment, followed by protein enrichment and enzymolysis. The protein enrichment is performed on the sample after the reductive alkylation treatment using a PVDF filter plate for protein enrichment; The invention also provides an automatic treatment system and an automatic sample treatment method. The treatment system greatly reduces the labor intensity of people, is beneficial to facilitate the treatment efficiency of urine sample treatment, meets the requirements of high-flux and automated pretreatment of the proteomics, and accommodates the reproducibility and flux of current clinical needs.

The method according to the present invention for preparing peptide fragments comprises bringing an antibody, which includes a Fc domain immobilized in pores of a porous body, into contact with a protease immobilized on surface of microparticles. Thus, the Fab domain of the antibody is site-specifically cleaved by the protease and a sample containing Fab domain-derived peptide fragments at a high concentration can be obtained. The protease to be used in the present invention is an animal-derived trypsin contaminated with chymotrypsin wherein the chymotrypsin is inactivated and the trypsin is chemically modified at amino group in lysine residues.

Pandemic COVID 19 causes global crisis in human health and economy. The pathogen of COVID 19, like the Influenzas causing common flus, belongs to a common type of virus called Ribonucleic Acid (RNA) virus. RNA viruses are composed of three structural components: genomic RNA, envelop and nuclear proteins, and bilayer lipid membrane. Targeting COVID 19 and all RNA viruses, the present invention describes an effective disinfectant system, which applies the combination of RNases, proteases, and detergents, at a broad range of concentration, pH, and temperature in the utilization, to eliminate the RNA viruses from any contaminated surfaces, airways, and filters. The disinfectant system provides an effective, convenient, environment friendly, and safe solution, for commercial and customer use, to disinfect RNA virus pathogens in concern.

Provided herein are methods, reagents, and kits for isolating polypeptides, such as a proteome. Also provided herein is a modified trypsin polypeptide that is resistant to autolysis, and that can be selectively-separated from a biological sample once digestion is complete.

The present invention discloses monodisperse protein-dendron conjugates that self-assemble to generation-dependent supramolecular protein assemblies of different size and surface charges. The invention further provides a process for synthesis of protein-dendron conjugates containing hydrophobic dendron of different generations.

Provided are: a protein degradation inducing tag which is a molecule that has affinity with proteases and does not inhibit degradation of a protein by proteases; a protein degradation inducing molecule that is a conjugate of at least one protein degradation inducing tag and at least one protein binding molecule that binds to a protein; and a usage of those.