A PHP Error was encountered

Severity: Warning

Message: file_get_contents(https://...@pubfacts.com&api_key=b8daa3ad693db53b1410957c26c9a51b4908&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests

Filename: helpers/my_audit_helper.php

Line Number: 176

Backtrace:

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 176
Function: file_get_contents

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 250
Function: simplexml_load_file_from_url

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 1034
Function: getPubMedXML

File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3152
Function: GetPubMedArticleOutput_2016

File: /var/www/html/application/controllers/Detail.php
Line: 575
Function: pubMedSearch_Global

File: /var/www/html/application/controllers/Detail.php
Line: 489
Function: pubMedGetRelatedKeyword

File: /var/www/html/index.php
Line: 316
Function: require_once

Isolation of a covalent steady-state intermediate in glutamate 60 mutants of thymidylate synthase. | LitMetric

Isolation of a covalent steady-state intermediate in glutamate 60 mutants of thymidylate synthase.

J Biol Chem

Department of Pharmaceutical Chemistry, University of California, San Francisco 94143-0448.

Published: December 1994

Glutamate 60 of thymidylate synthase coordinates a hydrogen bond network important in proton transfer reactions to and from the substrate dUMP. The E60A and E60L mutants of Lactobacillus casei thymidylate synthase catalyzed tritium exchange from [5-3H]dUMP for solvent protons faster than dTMP formation, indicating accumulation of a steady-state intermediate and a change in partitioning of the intermediate. A covalent complex consisting of E60A or E60L thymidylate synthase, dUMP, and the cofactor CH2H4 folate was isolated on SDS-polyacrylamide gel electrophoresis and shown to be chemically and kinetically competent to form dTMP. These results provide proof of the formation of a covalent steady-state intermediate in the reaction pathway of thymidylate synthase and demonstrate that the rate-determining step in the mutants occurs during conversion of the covalent intermediate to dTMP.

Download full-text PDF

Source

Publication Analysis

Top Keywords

thymidylate synthase
20
steady-state intermediate
12
covalent steady-state
8
e60a e60l
8
intermediate
5
thymidylate
5
synthase
5
isolation covalent
4
intermediate glutamate
4
glutamate mutants
4

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!