ADP-Ribosylation of variants of Azotobacter vinelandii dinitrogenase reductase by Rhodospirillum rubrum dinitrogenase reductase ADP-ribosyltransferase.
ADP-Ribosylation of variants of Azotobacter vinelandii dinitrogenase reductase by Rhodospirillum rubrum dinitrogenase reductase ADP-ribosyltransferase.
复制标题
红色红螺菌二硝基酶还原酶 ADP-核糖基转移酶对维氏固氮菌二硝基酶还原酶变体进行 ADP-核糖基化。
DOI：
10.1128/jb.182.9.2597-2603.2000
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发表时间：
2000
影响因子：
3.2
通讯作者：
Ludden,PW
中科院分区：
文献类型：
--
作者：
Grunwald,SK;Ryle,MJ;Lanzilotta,WN;Ludden,PW
在许多固氮细菌中，固氮酶受二固氮酶还原酶的可逆ADP-核糖基化的后序调节。来自棕色固氮菌的二氮酶还原酶的结构是已知的。在这项研究中，突变形式的二氮酶还原酶从A。测定了在各种蛋白质活性中受到影响的vinelandii被ADP-核糖基化或与来自红杜鹃的二氮酶还原酶ADP-核糖基转移酶（DRAT）形成复合物的能力。R140 Q二氮酶还原酶不能被DRAT进行ADP-核糖基化，但它仍能与DRAT形成一种交叉偶联复合物。因此，精氨酸140残基的二氮还原酶在ADP-核糖基化反应中起着关键作用。F135 Y取代或去除Fe 4S 4簇诱导的二氮酶还原酶构象变化导致二氮酶还原酶不成为ADP-核糖基化的底物。通过交联研究，还表明这些变化降低了二氮酶还原酶与DRAT形成交联复合物的能力。D129 E的取代或Leu 127的缺失，这会导致改变这些二氮酶还原酶的核苷酸结合区域，并没有显着改变二氮酶还原酶和DRAT之间的相互作用。以前的研究表明，将Lys 143变为Gln会降低二氮酶还原酶与二氮酶（L。C. Seefeldt，Protein Sci. 3：2073-2081，1994）;然而，这种变化对二氮酶还原酶和DRAT之间的相互作用没有实质性影响。
In a number of nitrogen-fixing bacteria, nitrogenase is posttranslationally regulated by reversible ADP-ribosylation of dinitrogenase reductase. The structure of the dinitrogenase reductase fromAzotobacter vinelandiiis known. In this study, mutant forms of dinitrogenase reductase fromA. vinelandiithat are affected in various protein activities were tested for their ability to be ADP-ribosylated or to form a complex with dinitrogenase reductase ADP-ribosyltransferase (DRAT) fromRhodospirillum rubrum. R140Q dinitrogenase reductase could not be ADP-ribosylated by DRAT, although it still formed a cross-linkable complex with DRAT. Thus, the Arg 140 residue of dinitrogenase reductase plays a critical role in the ADP-ribosylation reaction. Conformational changes in dinitrogenase reductase induced by an F135Y substitution or by removal of the Fe4S4cluster resulted in dinitrogenase reductase not being a substrate for ADP-ribosylation. Through cross-linking studies it was also shown that these changes decreased the ability of dinitrogenase reductase to form a cross-linkable complex with DRAT. Substitution of D129E or deletion of Leu 127, which result in altered nucleotide binding regions of these dinitrogenase reductases, did not significantly change the interaction between dinitrogenase reductase and DRAT. Previous results showed that changing Lys 143 to Gln decreased the binding between dinitrogenase reductase and dinitrogenase (L. C. Seefeldt, Protein Sci. 3:2073–2081, 1994); however, this change did not have a substantial effect on the interaction between dinitrogenase reductase and DRAT.