Beck B L, Tabatabai L B, Mayfield J E
U.S. Department of Agriculture, National Animal Disease Center, Ames, Iowa 50010.
Biochemistry. 1990 Jan 16;29(2):372-6. doi: 10.1021/bi00454a010.
Brucella abortus contains a protein that elicits an antigenic response in cattle previously exposed to the organism. The amino acid sequence of the recombinant form of this antigenic protein was determined by gas-phase sequencing of the pyridylethylated protein and its peptides obtained by digestion with cyanogen bromide (CNBr), clostripain, and Staphylococcus aureus V8 protease. The Brucella protein demonstrated 53.6% identity with the Cu-Zn superoxide dismutase (SOD) from Photobacterium leiognathi. Residues essential for metal coordination and enzymatic activity and cysteines required for the formation of the intrasubunit disulfide bridge of Cu-Zn SOD were conserved in the Brucella protein. also exhibited SOD activity that was inhibited by cyanide, which is characteristic of a Cu-Zn SOD. Brucella abortus Cu-Zn SOD is the second prokaryotic Cu-Zn SOD to be sequenced, and the fifth found in prokaryotes. The high degree of conservation between Photobacterium and Brucella Cu-Zn SOD supports the hypothesis of a separately evolved prokaryotic and eukaryotic Cu-Zn SOD gene.
流产布鲁氏菌含有一种能在先前接触过该微生物的牛体内引发抗原反应的蛋白质。通过对吡啶基乙基化蛋白质及其经溴化氰（CNBr）、梭菌蛋白酶和金黄色葡萄球菌V8蛋白酶消化得到的肽段进行气相测序，确定了这种抗原蛋白重组形式的氨基酸序列。布鲁氏菌蛋白与来自发光杆菌属的铜锌超氧化物歧化酶（SOD）具有53.6%的同一性。铜锌超氧化物歧化酶金属配位和酶活性所必需的残基以及亚基内二硫键形成所需的半胱氨酸在布鲁氏菌蛋白中是保守的。它还表现出被氰化物抑制的超氧化物歧化酶活性，这是铜锌超氧化物歧化酶的特征。流产布鲁氏菌铜锌超氧化物歧化酶是第二个被测序的原核铜锌超氧化物歧化酶，也是在原核生物中发现的第五个。发光杆菌属和布鲁氏菌属铜锌超氧化物歧化酶之间的高度保守支持了原核和真核铜锌超氧化物歧化酶基因分别进化的假说。
