PMID:6337635: Difference between revisions

From EcoliWiki
Jump to navigation Jump to search
New PMID: Page!
 
imported>Wikientrybot
change PMID template to TableEdit version
 
(7 intermediate revisions by 2 users not shown)
Line 1: Line 1:
<protect>
{{RightTOC}}
{{RightTOC}}
<!--box uid=d41d8cd98f00b204e9800998ecf8427e.112083.N5223963bb1ba8-->
<!--
******************************************************************************************
*
*  ** PLEASE DON'T EDIT THIS TABLE DIRECTLY.  Use the edit table link under the table. **
*
****************************************************************************************** -->
{|  id="N5223963bb1ba8"  class=" tableEdit PMID_info_table" 


<span style = 'font-size: large'> '''Baldwin, GS and Davidson, BE'''  (1983) Kinetic studies on the mechanism of chorismate mutase/prephenate dehydratase from Escherichia coli K12.''Biochim. Biophys. Acta'' '''742''':374-83</span>
|-
!align=left  |Citation
||
'''Baldwin, GS and Davidson, BE'''  (1983) Kinetic studies on the mechanism of chorismate mutase/prephenate dehydratase from Escherichia coli K12. ''Biochim. Biophys. Acta'' '''742''':374-83
|-
!align=left  |Abstract
||
The effect of pH on chorismate mutase/prephenate dehydratase (chorismate pyruvate mutase/prephenate hydro-lyase (decarboxylating) EC 5.4.99.5/EC 4.2.1.51) from Escherichia coli K12 has been studied. While the maximum velocity of both activities is independent of pH, Km for chorismate or prephenate shows a complex pH dependence. Differences in mutase activity in acetate/phosphate/borate and citrate/phosphate/borate buffers were traced to inhibition by citrate. When a variety of analogues of citrate were tested as possible inhibitors of the enzyme, several were found to inhibit mutase and dehydratase activities to different extents, and by different mechanisms. Thus citrate competitively inhibits mutase activity, but inhibits dehydratase activity by either a non-competitive or an uncompetitive mechanism. Conversely, cis- and trans-aconitate competitively inhibit dehydratase activity, but are partially competitive inhibitors of mutase activity. The differential effects of these inhibitors on the two activities are consistent with the existence of two distinct active sites, but additionally suggest some degree of interconnection between them. The implications of these results for possible mechanisms of catalysis by chorismate mutase/prephenate dehydratase are discussed.
|-
!align=left  |Links
||
[http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=6337635 PubMed]


{|{{Prettytable}} align = 'center' width= '70%'
|-
|-
|{{TableHeadingColor}} |'''Abstract''' || The effect of pH on chorismate mutase/prephenate dehydratase (chorismate pyruvate mutase/prephenate hydro-lyase (decarboxylating) EC 5.4.99.5/EC 4.2.1.51) from Escherichia coli K12 has been studied. While the maximum velocity of both activities is independent of pH, Km for chorismate or prephenate shows a complex pH dependence. Differences in mutase activity in acetate/phosphate/borate and citrate/phosphate/borate buffers were traced to inhibition by citrate. When a variety of analogues of citrate were tested as possible inhibitors of the enzyme, several were found to inhibit mutase and dehydratase activities to different extents, and by different mechanisms. Thus citrate competitively inhibits mutase activity, but inhibits dehydratase activity by either a non-competitive or an uncompetitive mechanism. Conversely, cis- and trans-aconitate competitively inhibit dehydratase activity, but are partially competitive inhibitors of mutase activity. The differential effects of these inhibitors on the two activities are consistent with the existence of two distinct active sites, but additionally suggest some degree of interconnection between them. The implications of these results for possible mechanisms of catalysis by chorismate mutase/prephenate dehydratase are discussed.
!align=left  |Keywords
</noinclude>
||
|-
Drug Stability; Escherichia coli/enzymology; Hydro-Lyases/metabolism; Hydrogen-Ion Concentration; Kinetics; Mathematics; Prephenate Dehydratase/metabolism; Substrate Specificity
|{{TableHeadingColor}} nowrap |'''Links''' ||  [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=6337635 PubMed]
 
|- class="tableEdit_footer"
|<span class="tableEdit_editLink plainlinks">[{{SERVER}}{{SCRIPTPATH}}?title=Special:TableEdit&id=d41d8cd98f00b204e9800998ecf8427e.112083.N5223963bb1ba8&page=112083&pagename={{FULLPAGENAMEE}}&type=1&template=PMID_info_table edit table]</span> ||
|}
|}
</protect>
<!--box uid=d41d8cd98f00b204e9800998ecf8427e.112083.N5223963bb1ba8-->
==Significance {{HelpIcon|Help:Literature}} ==
==Significance {{HelpIcon|Help:Literature}} ==
{{LitSignificance}}
{{LitSignificance}}
Line 19: Line 38:


==Annotations {{HelpIcon|Help:Literature}}==
==Annotations {{HelpIcon|Help:Literature}}==
<protect><!--box uid=63ce1649aab8b3180235b0af7618f667.0.P46c31cd13b701-->
<annotationlinks/>
<!--
******************************************************************************************
*
*  ** PLEASE DON'T EDIT THIS TABLE DIRECTLY.  Use the edit table link under the table. **
*
****************************************************************************************** -->
{|class = 'sortable' {{Prettytable}} id='220334'
|- {{table heading style}}
!Gene product!!Qualifier!!GO ID!!GO term name!!Evidence Code!!with/from!!Aspect!!Notes!!Status
|-class='sortbottom'
|[{{SERVER}}/colipedia/index.php?title=Special:TableEdit&id=63ce1649aab8b3180235b0af7618f667.0.P46c31cd13b701&page=0&pagename={{FULLPAGENAMEE}} edit table] || || || || || || || ||
|}
<!--box uid=63ce1649aab8b3180235b0af7618f667.0.P46c31cd13b701--></protect>


==EcoliWiki Links {{HelpIcon|Help:Literature}} ==
==EcoliWiki Links {{HelpIcon|Help:Literature}} ==

Latest revision as of 04:49, 15 September 2013

Citation

Baldwin, GS and Davidson, BE (1983) Kinetic studies on the mechanism of chorismate mutase/prephenate dehydratase from Escherichia coli K12. Biochim. Biophys. Acta 742:374-83

Abstract

The effect of pH on chorismate mutase/prephenate dehydratase (chorismate pyruvate mutase/prephenate hydro-lyase (decarboxylating) EC 5.4.99.5/EC 4.2.1.51) from Escherichia coli K12 has been studied. While the maximum velocity of both activities is independent of pH, Km for chorismate or prephenate shows a complex pH dependence. Differences in mutase activity in acetate/phosphate/borate and citrate/phosphate/borate buffers were traced to inhibition by citrate. When a variety of analogues of citrate were tested as possible inhibitors of the enzyme, several were found to inhibit mutase and dehydratase activities to different extents, and by different mechanisms. Thus citrate competitively inhibits mutase activity, but inhibits dehydratase activity by either a non-competitive or an uncompetitive mechanism. Conversely, cis- and trans-aconitate competitively inhibit dehydratase activity, but are partially competitive inhibitors of mutase activity. The differential effects of these inhibitors on the two activities are consistent with the existence of two distinct active sites, but additionally suggest some degree of interconnection between them. The implications of these results for possible mechanisms of catalysis by chorismate mutase/prephenate dehydratase are discussed.

Links

PubMed

Keywords

Drug Stability; Escherichia coli/enzymology; Hydro-Lyases/metabolism; Hydrogen-Ion Concentration; Kinetics; Mathematics; Prephenate Dehydratase/metabolism; Substrate Specificity

edit table

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

<annotationlinks/>

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.

Retrieved from "https://ecoliwiki.org/colipedia/index.php?title=PMID:6337635&oldid=1469315"