title: A variant peptide of buffalo colostrum β-lactoglobulin inhibits angiotensin I-converting enzyme activity.
abstract: β-lactoglobulin is a rich source of bioactive peptides. The LC-MS separated tryptic peptides of buffalo colostrum β-lactoglobulin (BLG-col) were computed based on MS-MS fragmentation for de novo sequencing. Among the selected peptides (P1-P8), a variant was detected with methionine at position 74 instead of glutamate. The sequences of two peptides were identical to hypocholesterolemic peptides whereas the remaining peptides were in accordance with buffalo milk β-lactoglobulin. Comparative sequence analysis of BLG-col to milk β-lactoglobulin was carried out using CLUSTALW2 and a molecular model for BLG-col was constructed (PMDB ID-PM0076812). The synthesized variant pentapeptide (IIAMK, m/z-576 Da) was found to inhibit angiotensin I-converting enzyme (ACE) with an IC(50) of 498 ± 2 μM, which was rationalized through docking simulations using Molgrow virtual docker.
authors.affiliation: Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka, India.
authors.forename: A C
authors.initials: AC
authors.lastname: Rohit
authors.forename: K
authors.initials: K
authors.lastname: Sathisha
authors.forename: H S
authors.initials: HS
authors.lastname: Aparna
mesh_terms: D000595:Amino Acid Sequence; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D000959:Antihypertensive Agents / Q000737:chemistry / Q000494:pharmacology*; D002020:Buffaloes; D002417:Cattle; D003126:Colostrum; D019295:Computational Biology; D005260:Female; D007782:Lactoglobulins / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D007703:Peptidyl-Dipeptidase A / Q000737:chemistry / Q000378:metabolism*; D011247:Pregnancy; D011487:Protein Conformation
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D007782:Lactoglobulins; D010446:Peptide Fragments; D007703:Peptidyl-Dipeptidase A