Molecular characterization of the ATPase component of a putative ABC type transporter in moraxella catarrhalis
Author(s)
Advisor
Ahmed, KamruddinDate
2004Publisher
Bilkent University
Language
English
Type
ThesisItem Usage Stats
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Abstract
Moraxella catarrhalis is one of the major causes of respiratory tract and middle ear
infections. Little is known about the pathogenesis of M. catarrhalis infection. A pathogenic
bacterium requires adherence, invasion, establishment and dissemination with the host for a
successful infection. The interaction between the host and the pathogen also includes uptake
and secretion of substances that are facilitated by a family of proteins termed transporters.
ATP-binding cassette (ABC) transporter is one of the active transport system common in
prokaryotic and eukaryotic cells. In this study, we identified a gene encoding ATPase
component of the ABC type transporter in M. catarrhalis and performed a nucleotide and
deduced amino acid sequence analysis of this gene. We used Genomic Survey Sequence
approach (GSS) to identify the gene from M. catarrhalis genomic library. The insert size of the
positive clone is 934 bp and was sequenced by DNA walking. The ATPase domain of an ABC
type transporter has conserved motifs: Walker A, Q loop, C loop (signature sequence), Walker
B, D loop and Switch II. The ATPase domain is considered as the most conserved domain of
the ABC type transporter due to presence of these motifs. Based on the homology and motif
search, and amino acid sequence alignment, performed by using BLAST programs available on
the internet, it was found that the deduced amino acid sequence encoded by this gene exhibited
50-80% identity with the sequences of the ATPase component of the ABC transporters of
several pathogens.
Keywords
Moraxella catarrhalisWalker B
Walker A
ATPase domain
ATP-binding cassette transporter
ABC type transporter