PMID:7601092: Difference between revisions

From EcoliWiki
Jump to navigation Jump to search
imported>Wikientrybot
Fix links due to TableEditLinks.php changes.
Update TableEdit tables.
Line 25: Line 25:
*  
*  
****************************************************************************************** -->
****************************************************************************************** -->
{|class = 'sortable' border="2" cellpadding="4" cellspacing="0" style="margin: 1em 1em 1em 0; border: 1px #aaa solid; border-collapse: collapse;"   
{|   id="C47aa94a0f3dad" class=" tableEdit GO_table_reference"   
|- {{table heading style}}
|-
!|Gene product!!Qualifier!!GO ID!!GO term name!!Evidence Code!!with/from!!Aspect!!Notes!!Status
!|Gene product!!Qualifier!!GO ID!!GO term name!!Evidence Code!!with/from!!Aspect!!Notes!!Status


|-class='sortbottom'
|- class="tableEdit_footer"
|[{{SERVER}}{{SCRIPTPATH}}?title=Special:TableEdit&id=63ce1649aab8b3180235b0af7618f667.0.C47aa94a0f3dad&page=0&pagename={{FULLPAGENAMEE}}&type=0&template=GO_table_reference edit table] || || || || || || || ||
|<span class="tableEdit_editLink plainlinks">[{{SERVER}}{{SCRIPTPATH}}?title=Special:TableEdit&id=63ce1649aab8b3180235b0af7618f667.0.C47aa94a0f3dad&page=0&pagename={{FULLPAGENAMEE}}&type=0&template=GO_table_reference edit table]</span> || || || || || || || ||
|}
|}
<!--box uid=63ce1649aab8b3180235b0af7618f667.0.C47aa94a0f3dad-->
<!--box uid=63ce1649aab8b3180235b0af7618f667.0.C47aa94a0f3dad-->

Revision as of 04:52, 9 January 2010

Maier, T, Lottspeich, F and Böck, A (1995) GTP hydrolysis by HypB is essential for nickel insertion into hydrogenases of Escherichia coli.Eur. J. Biochem. 230:133-8

Abstract The product of the hypB gene, which is required for the maturation of the three [NiFe]hydrogenases of Escherichia coli, is a member of the GTPase family and exhibits a low intrinsic GTPase activity. It was studied whether or not GTP hydrolysis by HypB is coupled to nickel insertion into hydrogenases and to maturation of hydrogenases. Mutations were introduced into the hypB gene at sites expected to code for amino acids involved in guanine-nucleotide binding. Lys117 of G-motif 1, as well as Asp241 of G-motif 4 were substituted by asparagine residues. The purified mutant HypB proteins showed strongly reduced, but still significant, GTPase activity. In the case of [D241N]HypB, the kcat/Km value was lowered by a factor of 85 and the specificity of the enzyme for GTP was apparently lost, with other nucleoside triphosphates including XTP becoming compatible substrates. The decrease in GTPase activity was even more pronounced for [K117N]HypB. To assess the functionality of these HypB proteins in vivo, the wild-type hypB gene in the chromosome of E. coli was replaced by the mutant alleles. The resulting mutant strains BKN117 and BDN241 were affected in hydrogen metabolism under fermentative conditions. BKN117 did not display hydrogenase activity due to a loss of nickel incorporation into the large subunit. BDN241 exhibited a reduction of hydrogenase activity by 44% and only a portion of the hydrogenase 3 large subunit was in the mature nickel-containing form. From these results, it is concluded that GTP hydrolysis catalysed by HypB is an integral process in nickel incorporation into hydrogenases.
Links PubMed

Significance

You can help EcoliWiki by summarizing why this paper is useful

Useful Materials and Methods

You can help Ecoliwiki by describing the useful materials (strains, plasmids, antibodies, etc) described in this paper.

Annotations

Gene product Qualifier GO ID GO term name Evidence Code with/from Aspect Notes Status

EcoliWiki Links

Add links to pages that link here (e.g. gene, product, method pages)

References

See Help:References for how to manage references in EcoliWiki.