Format

Send to

Choose Destination
BMC Microbiol. 2014 Dec 21;14:330. doi: 10.1186/s12866-014-0330-3.

Chlamydia pneumoniae effector chlamydial outer protein N sequesters fructose bisphosphate aldolase A, providing a benefit to bacterial growth.

Author information

1
Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido, 060-0812, Japan. kasumi_ishida@ec.hokudai.ac.jp.
2
Research Fellow of Japan Society for the Promotion of Science, Tokyo, 102-0083, Japan. kasumi_ishida@ec.hokudai.ac.jp.
3
Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido, 060-0812, Japan. matsuo@hs.hokudai.ac.jp.
4
Department of Biomedical Informatics, Osaka University Graduate School of Medicine, Suita, Osaka, 565-0871, Japan. yyamamoto@iph.pref.osaka.jp.
5
Japan Science and Technology Agency/Japan International Cooperation Agency, Science and Technology Research Partnership for Sustainable Development (JST/JICA, SATREPS), Osaka, Japan. yyamamoto@iph.pref.osaka.jp.
6
Osaka Prefectural Institute of Public Health, Higashinari-ku, Osaka, 537-0025, Japan. yyamamoto@iph.pref.osaka.jp.
7
Department of Medical Laboratory Science, Faculty of Health Sciences, Hokkaido University, Sapporo, Hokkaido, 060-0812, Japan. hiroyuki@med.hokudai.ac.jp.

Abstract

BACKGROUND:

Pathogenic chlamydiae are obligate intracellular pathogens and have adapted successfully to human cells, causing sexually transmitted diseases or pneumonia. Chlamydial outer protein N (CopN) is likely a critical effector protein secreted by the type III secretion system in chlamydiae, which manipulates host cells. However, the mechanisms of its action remain to be clarified. In this work, we aimed to identify previously unidentified CopN effector target in host cells.

RESULTS:

We first performed a pull-down assay with recombinant glutathione S-transferase (GST) fusion CopN proteins (GST-CpCopN: Chlamydia pneumoniae TW183, GST-CtCopN: Chlamydia trachomatis D/UW-3/CX) as "bait" and soluble lysates obtained from human immortal epithelial HEp-2 cells as "prey", followed by SDS-PAGE with mass spectroscopy (MS). We found that a host cell protein specifically bound to GST-CpCopN, but not GST-CtCopN. MS revealed the host protein to be fructose bisphosphate aldolase A (aldolase A), which plays a key role in glycolytic metabolism. We also confirmed the role of aldolase A in chlamydia-infected HEp-2 cells by using two distinct experiments for gene knockdown with an siRNA specific to aldolase A transcripts, and for assessment of glycolytic enzyme gene expression levels. As a result, both the numbers of chlamydial inclusion-forming units and RpoD transcripts were increased in the chlamydia-infected aldolase A knockdown cells, as compared with the wild-type HEp-2 cells. Meanwhile, chlamydial infection tended to enhance expression of aldolase A.

CONCLUSIONS:

We discovered that one of the C. pneumoniae CopN targets is the glycolytic enzyme aldolase A. Sequestering aldolase A may be beneficial to bacterial growth in infected host cells.

PMID:
25528659
PMCID:
PMC4302594
DOI:
10.1186/s12866-014-0330-3
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for BioMed Central Icon for PubMed Central
Loading ...
Support Center