title: Enzymatic synthesis and characterization of l-methionine and 2-hydroxy-4-(methylthio)butanoic acid (HMB) co-oligomers.
abstract: Oligomers of l-methionine (Met) and its hydroxy analogue, 2-hydroxy-4-(methylthio)butanoic acid (d,l-HMB) were synthesized with the proteolytic enzyme papain. The Met homooligomers and HMB-Met co-oligomers obtained through the enzymatic reactions were subjected to persulfonation and separated with reverse phase liquid chromatography (RPLC). The separated oligomers were characterized with electrospray ionization-mass spectrometry (ESI-MS). The oligomers were also characterized with matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). The results showed that co-oligomers were predominantly composed of 4-8 Met residues and one HMB residue. The data also suggest that in the co-oligomers, HMB is attached at the N-terminal end of the oligopeptide chain.
authors.affiliation: Center for Environmental Science and Technology and Department of Chemistry, University of Missouri-Rolla, 1870 Miner Circle, Rolla, Missouri 65409-0530, USA.
authors.forename: Mathur
authors.initials: M
authors.lastname: Rajesh
authors.forename: Shubhen
authors.initials: S
authors.lastname: Kapila
authors.forename: Paul
authors.initials: P
authors.lastname: Nam
authors.forename: Daniel
authors.initials: D
authors.lastname: Forciniti
authors.forename: Stephen
authors.initials: S
authors.lastname: Lorbert
authors.forename: Charles
authors.initials: C
authors.lastname: Schasteen
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D008715:Methionine / Q000031:analogs & derivatives* / Q000032:analysis* / Q000096:biosynthesis; D010206:Papain / Q000378:metabolism*
chemical_list: C008391:alpha-hydroxy-gamma-methylmercaptobutyric acid; D008715:Methionine; D010206:Papain