title: Structure of nitrilotriacetate monooxygenase component B from Mycobacterium thermoresistibile.
abstract: Mycobacterium tuberculosis belongs to a large family of soil bacteria which can degrade a remarkably broad range of organic compounds and utilize them as carbon, nitrogen and energy sources. It has been proposed that a variety of mycobacteria can subsist on alternative carbon sources during latency within an infected human host, with the help of enzymes such as nitrilotriacetate monooxygenase (NTA-Mo). NTA-Mo is a member of a class of enzymes which consist of two components: A and B. While component A has monooxygenase activity and is responsible for the oxidation of the substrate, component B consumes cofactor to generate reduced flavin mononucleotide, which is required for component A activity. NTA-MoB from M. thermoresistibile, a rare but infectious close relative of M. tuberculosis which can thrive at elevated temperatures, has been expressed, purified and crystallized. The 1.6 Å resolution crystal structure of component B of NTA-Mo presented here is one of the first crystal structures determined from the organism M. thermoresistibile. The NTA-MoB crystal structure reveals a homodimer with the characteristic split-barrel motif typical of flavin reductases. Surprisingly, NTA-MoB from M. thermoresistibile contains a C-terminal tail that is highly conserved among mycobacterial orthologs and resides in the active site of the other protomer. Based on the structure, the C-terminal tail may modulate NTA-MoB activity in mycobacteria by blocking the binding of flavins and NADH.
authors: Seattle Structural Genomics Centre for Infectious Disease (SSGCID), USA. sunny.zhang@seattlebiomed.org
authors: Y
authors: Y
authors: Zhang
authors: T E
authors: TE
authors: Edwards
authors: D W
authors: DW
authors: Begley
authors: A
authors: A
authors: Abramov
authors: K B
authors: KB
authors: Thompkins
authors: M
authors: M
authors: Ferrell
authors: W J
authors: WJ
authors: Guo
authors: I
authors: I
authors: Phan
authors: C
authors: C
authors: Olsen
authors: A
authors: A
authors: Napuli
authors: B
authors: B
authors: Sankaran
authors: R
authors: R
authors: Stacy
authors: W C
authors: WC
authors: Van Voorhis
authors: L J
authors: LJ
authors: Stewart
authors: P J
authors: PJ
authors: Myler
mesh_terms: D000595:Amino Acid Sequence; D017124:Conserved Sequence; D006899:Mixed Function Oxygenases / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009161:Mycobacterium / Q000201:enzymology*; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D006899:Mixed Function Oxygenases; C072680:nitrilotriacetate monooxygenase