Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2005-4-19
pubmed:abstractText
Members of the genus Chlamydia lack a peptidoglycan layer. As a substitute for peptidoglycan, it has been proposed that several cysteine rich proteins, including the major outer membrane protein (MOMP), form disulfide bonds to provide rigidity to the cell wall. Alignment of the amino acids sequences of the MOMP from various serovars of Chlamydia showed that they have from 7 to 10 cysteine residues and seven of them are highly conserved. Which of these are free cysteine residues and which are involved in disulfide bonds is unknown. The complexity of the outer membrane of Chlamydia precludes at this point the characterization of the structure of the cysteines directly in the bacteria. Therefore, mass spectrometric analysis of a purified and refolded MOMP was used in this study. Characterization of the structure of this preparation of the MOMP is critical because it has been shown, in an animal model, to be a very effective vaccine against respiratory and genital infections. Here, we demonstrated that in this MOMP preparation four cysteines are involved in disulfide bonds, with intramolecular pairs formed between Cys(48) and Cys(55) and between Cys(201) and Cys(203). A stepwise alkylation, reduction, alkylation process using two different alkylating reagents was required to establish the Cys(48)-Cys(55) disulfide pair. The other residues in MOMP, Cys(51), Cys(136), Cys(226), and Cys(351), are free cysteines and could potentially form disulfide-linked complexes with other MOMP or other membrane proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6250-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Characterization of the disulfide bonds and free cysteine residues of the Chlamydia trachomatis mouse pneumonitis major outer membrane protein.
pubmed:affiliation
Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132, USA. ryen@sfsu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.