|Ref Sequence Id||NP_001002237.1|
|Amino Acid Lenth||321|
|Protein Existence Status||Reviewed: Experimental evidence at protein level|
|Protein Function||collagen containing C type lectin; CL-43 is synthesized only in the bovine liver; involved in the innate immune defense; bind to microbial surface carbohydrates inducing aggregation and, thereby, impeding infectivity; binds to the collectin receptor (C1qR) localized on many types of cells identified as a surface variant of calreticulin; show antiviral activities towards influenza A virus and rotaviruses ; displays protective activity against bacterial infections|
|Biochemical Properties||collectins – family of oligomeric proteins composed of trimeric subunits containing collagen-like sequences joined to C-type lectin domains; presence of collagen- like sequences and globular carbohydrate recognition domains; CL-43 has 1 trimeric unit; trimeric subunits are stabilized by noncovalent interactions (strong hydrophobic forces in α-helical bundle) and covalently by disulfide bridges between cysteine residues in the N-terminal or collagen regions; binds to carbohydrates in the presence of calcium ions; Collectin-43 is found only as a single subunit composed of three identical polypeptide chains; in 2D PAGE CL-43 is seen as two isoforms, with pI (isoelectric point) values of 4.9 and 5.3, corresponding to the native and the truncated form of the molecule; CL-43 binds to a range of sugar residues including mannose, fucose, glucose, maltose, GlcNAc or ManNAc with highest affinity for mannose; binding of carbohydrates involves hydrogen bonds and van der Waal’s interactions, and is stabilized by coordination bonds to the calcium ions|
|Significance in milk||Antimicrobial proteins - exclusively detected in the colostrum fluid phase|
|PTMs||CL -43 does not posses N-linked carbohydrate, but it contains hydroxylysine residues in the collagen-like region that are potential O-glycosylation sites|
|Bibliography||1. Nissen, A., Andersen, P. H., Bendixen, E., Ingvartsen, K. L., and Røntved, C. M. (2017) Colostrum and milk protein rankings and ratios of importance to neonatal calf health using a proteomics approach. J. Dairy Sci. 100, 2711–2728. |
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