THE TERMINAL REDUCTASES FOR SELENATE AND NITRATE RESPIRATION IN THAUERA-SELENATIS ARE 2 DISTINCT ENZYMES

被引：60

作者：

RECH, SA ^{[1
]}

MACY, JM ^{[1
]}

机构：

[1] UNIV CALIF DAVIS,DEPT ANIM SCI,DAVIS,CA 95616

来源：

JOURNAL OF BACTERIOLOGY | 1992年 / 174卷 / 22期

关键词：

D O I：

10.1128/jb.174.22.7316-7320.1992

中图分类号：

Q93 [微生物学];

学科分类号：

071005 ; 100705 ;

摘要：

A number of approaches have been used to show that a recently isolated selenate-respiring bacterium, Thauera selenatis, is able to synthesize both a selenate reductase (SR) and a nitrate reductase (NR). (i) The pH optimum of the SR was found to be 6.0; that of the NR was 7.0. (ii) The presence of nitrate did not inhibit selenate reduction in selenate-grown cells. (iii) In cell extracts, the highest SR or NR activity was observed in cells grown with the respective electron acceptor. (iv) Mutants that were unable to grow with nitrate as the terminal electron acceptor and lacked NR activity were isolated; these mutants grew normally with selenate and synthesized SR. (v) The SR was found in the periplasmic space of the cell, whereas the NR was present in the cytoplasmic membrane. A hypothetical electron transport system involving the SR is described.

引用

页码：7316 / 7320

页数：5

共 18 条

[1]

BARNES JM, 1992, 92ND GEN M AM SOC MI

[2]

COYNE MS, 1990, FEMS S, V56, P21

[3]

DEMOLLDECKER H, UNPUB

[4]

Gottschalk G., 1986, BACTERIAL METABOLISM