title: Expression and characterization of a second L-amino acid deaminase isolated from Proteus mirabilis in Escherichia coli.
abstract: L-amino acid deaminases catalyze the deamination of natural L-amino acids. Two types of L-amino acid deaminase have been identified in Proteus species. One exhibits high levels of activity toward a wide range of aliphatic and aromatic L-amino acids, typically L-phenylalanine, whereas the other acts on a relatively narrow range of basic L-amino acids, typically L-histidine. In this study, we cloned, expressed, and characterized a second amino acid deaminase, termed Pm1, from P. mirabilis KCTC 2566. Homology alignment of the deduced amino acid sequence of Pm1 demonstrated that the greatest similarity (96%) was with the L-amino acid deaminase (LAD) of P. vulgaris, and that homology with Pma was relatively low (72%). Also, similar to LAD, Pm1 was most active on L-histidine, indicating that Pm1 belongs to the second type of amino acid deaminase. In agreement with this conclusion, the V(max) and K(m) values of Pm1 were 119.7 (μg phenylpyruvic acid/mg/min) and 31.55 mM phenylalanine, respectively, values lower than those of Pma. The Pml deaminase will be very useful industrially in the preparation of commercially valuable materials including urocanic acid and α-oxoglutarate.
authors.affiliation: Microbe-based Fusion Technology Research Center, Jeonbuk Branch Institute, Korea Research Institute of Bioscience and Biotechnology KRIBB, Jeongeup, Jeonbuk, South Korea.
authors.forename: Jin-Oh
authors.initials: JO
authors.lastname: Baek
authors.forename: Jeong-Woo
authors.initials: JW
authors.lastname: Seo
authors.forename: Ohsuk
authors.initials: O
authors.lastname: Kwon
authors.forename: Su-Il
authors.initials: SI
authors.lastname: Seong
authors.forename: Ik-Hwan
authors.initials: IH
authors.lastname: Kim
authors.forename: Chul Ho
authors.initials: CH
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D000642:Ammonia-Lyases / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D007700:Kinetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011513:Proteus mirabilis / Q000201:enzymology* / Q000235:genetics; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D004269:DNA, Bacterial; D011994:Recombinant Proteins; D000642:Ammonia-Lyases