Isolation of Mn-SOD and low active Fe-SOD from Methylomonas J; consisting of identical proteins.
Cultures of Methylomonas J, an aerobic methylotrophic bacterium, were grown both in Mn-rich and Fe-rich media. Crude extracts of the cultures from the Mn-rich and Fe-rich medium showed a specific activity of 12.2 and 0.6 units/mg by a cytochrome c-xanthine oxidase method and 19.4 and 1.3 units/mg by an ESR method, respectively. We isolated Mn-SOD and Fe-SOD from the bacteria grown in the Mn-rich and Fe-rich mediums, respectively. Specific activity and metal contents of the Mn-enzyme were 2,250 units/mg/g-atom Mn and Mn = 0.98 and Fe = 0.12 (g-atoms/mol dimer), while those of the Fe-enzyme were 61 units/mg/g-atom Fe and Mn = 0.02 and Fe = 1.08. No difference of physicochemical properties of the Fe- and Mn-enzymes were detected. Furthermore, enzyme activity was restored by dialysis of an apoprotein obtained from the Fe-enzyme with either manganese sulfate or ferrous ammonium sulfate.
Yamakura
F
F
Department of Chemistry, Juntendo University, Chiba, Japan.
Matsumoto
T
T
Terauchi
K
K
D000595:Amino Acid Sequence; D001059:Apoproteins / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D007501:Iron; D008345:Manganese; D008772:Methylococcaceae / Q000201:enzymology* / Q000235:genetics; D008969:Molecular Sequence Data; D013482:Superoxide Dismutase / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism
D001059:Apoproteins; D001426:Bacterial Proteins; D008345:Manganese; D007501:Iron; D013482:Superoxide Dismutase