This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.


1nhq

From Proteopedia

(Difference between revisions)
Jump to: navigation, search
Line 1: Line 1:
-
[[Image:1nhq.jpg|left|200px]]
+
{{Seed}}
 +
[[Image:1nhq.png|left|200px]]
<!--
<!--
Line 9: Line 10:
{{STRUCTURE_1nhq| PDB=1nhq | SCENE= }}
{{STRUCTURE_1nhq| PDB=1nhq | SCENE= }}
-
'''CRYSTALLOGRAPHIC ANALYSES OF NADH PEROXIDASE CYS42ALA AND CYS42SER MUTANTS: ACTIVE SITE STRUCTURE, MECHANISTIC IMPLICATIONS, AND AN UNUSUAL ENVIRONMENT OF ARG303'''
+
===CRYSTALLOGRAPHIC ANALYSES OF NADH PEROXIDASE CYS42ALA AND CYS42SER MUTANTS: ACTIVE SITE STRUCTURE, MECHANISTIC IMPLICATIONS, AND AN UNUSUAL ENVIRONMENT OF ARG303===
-
==Overview==
+
<!--
-
NADH peroxidase from Enterococcus faecalis is a tetrameric flavoenzyme of 201,400 Da which employs Cys 42 as a redox-active center cycling between sulfhydryl (Cys-SH) and sulfenic acid (Cys-SOH) states along the catalytic pathway. The role of the active site cysteine 42 in NADH peroxidase has been elucidated using biochemical and crystallographic techniques. Here we describe the crystal structures of two active site cysteine mutants, Cys42Ala and Cys42Ser, which were determined to 2.0 A resolution and refined to crystallographic R values of 17.6 and 18.3%, respectively. The overall chain fold and the quaternary structure of the two mutants appear to be very similar to wild-type enzyme. Therefore, the substantially lower activity of the mutants is due to the absence of the Cys-SOH redox center. One of the oxygen atoms of the nonnative cysteine sulfonic acid in the wild-type structure is replaced by a water molecule in both mutant structures. Two other residues near the active site are His 10 and Arg 303. A detailed analysis of the environment of these residues in the mutant and wild-type peroxidase structures indicates that the imidazole ring of His 10 is uncharged. The interactions made by the guanidinium group of Arg 303 involve not only His 10 but also the carboxylate of Glu 14 and Tyr 60. Interestingly, the Nn1H function of Arg 303 is oriented perpendicular to the plane of the phenyl ring of Tyr 60 with a Nn1 to phenyl ring center distance of 3.8 A, suggesting a favorable electrostatic interaction between Arg 303 and Tyr 60.(ABSTRACT TRUNCATED AT 250 WORDS)
+
The line below this paragraph, {{ABSTRACT_PUBMED_7766608}}, adds the Publication Abstract to the page
 +
(as it appears on PubMed at http://www.pubmed.gov), where 7766608 is the PubMed ID number.
 +
-->
 +
{{ABSTRACT_PUBMED_7766608}}
==About this Structure==
==About this Structure==
Line 26: Line 30:
[[Category: Hol, W G.J.]]
[[Category: Hol, W G.J.]]
[[Category: Mande, S S.]]
[[Category: Mande, S S.]]
-
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 02:32:37 2008''
+
 
 +
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Tue Jul 29 09:22:44 2008''

Revision as of 06:22, 29 July 2008

Image:1nhq.png

Template:STRUCTURE 1nhq

CRYSTALLOGRAPHIC ANALYSES OF NADH PEROXIDASE CYS42ALA AND CYS42SER MUTANTS: ACTIVE SITE STRUCTURE, MECHANISTIC IMPLICATIONS, AND AN UNUSUAL ENVIRONMENT OF ARG303

Template:ABSTRACT PUBMED 7766608

About this Structure

1NHQ is a Single protein structure of sequence from Enterococcus faecalis. Full crystallographic information is available from OCA.

Reference

Crystallographic analyses of NADH peroxidase Cys42Ala and Cys42Ser mutants: active site structures, mechanistic implications, and an unusual environment of Arg 303., Mande SS, Parsonage D, Claiborne A, Hol WG, Biochemistry. 1995 May 30;34(21):6985-92. PMID:7766608

Page seeded by OCA on Tue Jul 29 09:22:44 2008

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/1nhq"
Personal tools