Three-dimensional structure of manganese superoxide dismutase from Bacillus halodenitrificans, a component of the so-called "green protein".
A so-called "green protein" has been purified from a moderate halophilic eubacterium, Bacillus halodenitrificans (ATCC 49067), under anaerobic conditions. The protein, which might play an important role in denitrification, dissociates mainly into two components after exposure to air: a manganese superoxide dismutase (GP-MnSOD) and a nucleoside diphosphate kinase. As a first step in elucidating the overall structure of the green protein and the role of each component, the 2.8-A resolution crystal structure of GP-MnSOD was determined. Compared with other manganese dismutases, GP-MnSOD shows two significant characteristics. The first is that the entrance to its substrate channel has an additional basic residue-Lys38. The second is that its surface is decorated with an excess of acidic over basic residues. All these structural features may be related to GP-MnSOD's high catalytic activity and its endurance against the special cytoplasm of B. halodenitrificans. The structure of GP-MnSOD provides the basis for recognizing its possible role and assembly state in the green protein.
Liao
Jun
J
National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing, China.
Liu
Ming Yih
MY
Chang
Tschining
T
Li
Mei
M
Le Gall
Jean
J
Gui
Lu Lu
LL
Zhang
Ji Ping
JP
Jiang
Tao
T
Liang
Dong Cai
DC
Chang
Wen Rui
WR
D000595:Amino Acid Sequence; D001407:Bacillus / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D001665:Binding Sites; D002384:Catalysis; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020836:Protein Structure, Quaternary; D012492:Salts / Q000494:pharmacology; D017386:Sequence Homology, Amino Acid; D055672:Static Electricity; D013329:Structure-Activity Relationship; D013482:Superoxide Dismutase / Q000737:chemistry* / Q000378:metabolism; D015032:Zinc / Q000378:metabolism
D001426:Bacterial Proteins; D012492:Salts; D013482:Superoxide Dismutase; D015032:Zinc