title: Identification and initial characterization of a putative Mycoplasma gallinarum leucine aminopeptidase gene.
abstract: Aminopeptidases (APN) may play a role in host colonization of M. gallinarum. Characterization of endogenous APN activity suggests that the leucine APN (LAP) of M. gallinarum is a metallo-aminopeptidase activated by Mn2+ and is present in the cytosol and possibly associated with the inner leaflet of the membrane. A 1.36-kb open reading frame (ORF) identified from overlapping genomic phage clones showed 68% nucleotide identity and 51% amino acid identity with the M. salivarium LAP gene. This ORF is expressed as a 1.5-kb monocistronic transcript and is present as a single copy in M. gallinarum. This gene sequence was modified to account for codon usage, and expression in E. coli produced a 51-kDa protein, which compares well with the product predicted from the ORF. This ORF is a strong candidate for contributing the LAP activity of M. gallinarum protein extracts.
authors.affiliation: Department of Basic Sciences, College of Veterinary Medicine, Box 6100, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Xiufeng
authors.initials: X
authors.lastname: Wan
authors.forename: Scott L
authors.initials: SL
authors.lastname: Branton
authors.forename: Larry A
authors.initials: LA
authors.lastname: Hanson
authors.forename: Gregory T
authors.initials: GT
authors.lastname: Pharr
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015723:Gene Library; D007931:Leucyl Aminopeptidase / Q000235:genetics* / Q000302:isolation & purification*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009174:Mycoplasma / Q000201:enzymology* / Q000235:genetics*; D012329:RNA, Bacterial / Q000737:chemistry / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment
chemical_list: D004269:DNA, Bacterial; D012329:RNA, Bacterial; D011994:Recombinant Proteins; D007931:Leucyl Aminopeptidase