title: [Physiological and biochemical characteristics of a manganese catalase lacking n-terminal].
abstract: OBJECTIVE
  We characterizeda manganese catalase lacking n-terminal ( MnCAT-C), to revealits roles in bacterial growth, reactive oxygen species ( ROS) removal and degradation of polychlorinated biphenyls ( PCBs) in Rhodococcus sp. R04.
  
  
  METHODS
  Manganese catalase (Mn-CAT) sequence of the strain R04 was aligned with that of Rhodococcus sp. R11101. Mn-CAT and MnCAT-C were expressed in E. coli BL21 (DE3), and the target protein was purified with Q-sepharose and ammonium sulphate precipitation. Knockout strain was obtained by homologous recombination. ROS was measured by fluorescence polarization, and the degradation rate of PCBs was measured by HPLC. [Results] MnCAT-C protein was purified, and SDS-PAGE analysis showed that its molecular weight was 23 kDa. Compared with wild strains, the ROS concentration increased, and the growth rate was inhibited in knockout strains. Moreover, the degradationrate of PCBs decreased. [Conclusion] MnCAT-C retained the majority of the active properties of the original enzyme, including ROS clearance. The lack of MnCAT-C gene affected the growth rate and the PCBsdegradationrate instrain R04.
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Yang
authors.forename: Yang
authors.initials: Y
authors.lastname: Wang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002374:Catalase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017434:Protein Structure, Tertiary; D012240:Rhodococcus / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D016415:Sequence Alignment; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D002374:Catalase