title: Isolation, purification, and characterization of avian antimicrobial glycopeptide from the posterior salivary gland of Sepia pharaonis.
abstract: A proteinaceous glycopeptide was isolated from the posterior salivary gland (PSG) of Sepia pharaonis by gel (Sephadex G-100) filtration chromatography and purified by reversed-phase high-performance liquid chromatography (RP-HPLC). Among the collected fractions, fraction 12 showed a retention time (RT) of 31 min. The total protein and neutral sugar contents of the purified glycopeptide were recorded as 68.14 and 2.95 mg, respectively. The molecular weight of the purified glycopeptide was found to be ~50 kDa. The infrared (IR) and circular dichroism (CD) spectroscopy confirmed the presence of peptide and secondary structure in the purified glycopeptide. The antibacterial activity of the purified glycopeptide against avian bacterial strains was also determined. Gas chromatography-mass spectrometry (GC-MS) of the purified glycopeptide revealed the likely compounds for the antibacterial activity such as 22, 23-dibromostigmasterol acetate, 3-methyl 2-(2-oxypropyl) furan, and 2,4,4-trimethyl-3-hydroxymethyl-5A-(3-methyl-but-2-enyl)-cyclohexene. These three compounds found in the purified glycopeptide could be responsible for the antibacterial activity against the avian pathogens. The results of this study suggest that the purified glycopeptide from the PSG of S. pharaonis could be an antibacterial agent against avian bacterial pathogens.
authors.affiliation: Department of Medical Biotechnology, Faculty of Allied Health Sciences, Chettinad Hospital and Research Institute, Kelambakkam, Chennai, Tamil Nadu, 603 103, India.
authors.forename: R
authors.initials: R
authors.lastname: Karthik
authors.forename: R
authors.initials: R
authors.lastname: Saravanan
authors.forename: K Kumar
authors.initials: KK
authors.lastname: Ebenezar
authors.forename: T
authors.initials: T
authors.lastname: Sivamalai
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D005591:Chemical Fractionation; D002645:Chickens; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D002942:Circular Dichroism; D004591:Electrophoresis, Polyacrylamide Gel; D006020:Glycopeptides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D008970:Molecular Weight; D012469:Salivary Glands / Q000737:chemistry*; D049833:Sepia / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013997:Time Factors
chemical_list: D000900:Anti-Bacterial Agents; D006020:Glycopeptides