Fersiynau electronig

Dangosydd eitem ddigidol (DOI)

  • Yijun Zhu
    The University of Warwick
  • Eleanor Jameson
    University of Warwick
  • Rosemary A Parslow
    School of Sport and Exercise Sciences, University of Birmingham
  • Ian Lidbury
    University of Warwick
  • Tiantian Fu
    University of Warwick
  • Timothy R Dafforn
    School of Sport and Exercise Sciences, University of Birmingham
  • Hendrik Schäfer
    University of Warwick
  • Yin Chen
    University of Warwick

Methylocella silvestris, an alphaproteobacterium isolated from a forest soil, can grow on trimethylamine N-oxide (TMAO) as a sole nitrogen source; however, the molecular and biochemical mechanisms underpinning its growth remain unknown. Marker-exchange mutagenesis enabled the identification of several genes involved in TMAO metabolism, including Msil_3606, a permease of the amino acids-polyamine (APC) superfamily, and Msil_3603, consisting of an N-terminal domain of unknown function (DUF1989) and a C-terminal tetrahydrofolate-binding domain. Null mutants of Msil_3603 and Msil_3606 can no longer grow on TMAO. Purified Msil_3603 from recombinant Escherichia coli can convert TMAO to dimethylamine and formaldehyde (1 TMAO → 1 dimethylamine + 1 formaldehyde), confirming that it encodes a bona fide TMAO demethylase (Tdm). Tdm of M. silvestris and eukaryotic Tdms have no sequence homology and contrasting characteristics. Recombinant Tdm of M. silvestris appears to be hexameric, has a high affinity for TMAO (Km = 3.3 mM; Vmax = 21.7 nmol min(-1)  mg(-1) ) and only catalyses demethylation of TMAO and a structural homologue, dimethyldodecylamine N-oxide. Our study has contributed to the understanding of the genetic and biochemical mechanisms for TMAO degradation in M. silvestris.

Allweddeiriau

Iaith wreiddiolSaesneg
Tudalennau (o-i)3318-30
Nifer y tudalennau13
CyfnodolynEnvironmental Microbiology
Cyfrol16
Rhif y cyfnodolyn10
Dyddiad ar-lein cynnar3 Awst 2014
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 1 Hyd 2014
Cyhoeddwyd yn allanolIe
Gweld graff cysylltiadau