title: Roles of Ala-149 in the catalytic activity of diadenosine tetraphosphate phosphorylase from Mycobacterium tuberculosis H37Rv.
abstract: Diadenosine 5',5'''-P(1),P(4)-tetraphosphate (Ap4A) phosphorylase from Mycobacterium tuberculosis H37Rv (MtAPA) belongs to the histidine triad motif (HIT) superfamily, but is the only member with an alanine residue at position 149 (Ala-149). Enzymatic analysis revealed that the Ala-149 deletion mutant displayed substrate specificity for diadenosine 5',5'''-P(1),P(5)-pentaphosphate and was inactive on Ap4A and other substrates that are utilized by the wild-type enzyme.
authors.affiliation: a Department of Bacteriology II , National Institute of Infectious Diseases , Musashi-Murayama , Japan.
authors.forename: Shigetarou
authors.initials: S
authors.lastname: Mori
authors.forename: Hyun
authors.initials: H
authors.lastname: Kim
authors.forename: Emiko
authors.initials: E
authors.lastname: Rimbara
authors.forename: Yoshichika
authors.initials: Y
authors.lastname: Arakawa
authors.forename: Keigo
authors.initials: K
authors.lastname: Shibayama
mesh_terms: D000409:Alanine; D000595:Amino Acid Sequence; D055162:Biocatalysis; D020134:Catalytic Domain; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009169:Mycobacterium tuberculosis / Q000201:enzymology*; D009713:Nucleotidyltransferases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D009713:Nucleotidyltransferases; C044740:diadenosine 5,5'''-P(1),P(4)-tetraphosphate alpha,beta-phosphorylase; D000409:Alanine
keywords: drug target; kinetics; mycobacteria; phosphorylase