{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T20:19:50Z","timestamp":1775506790436,"version":"3.50.1"},"reference-count":81,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2018,6,11]],"date-time":"2018-06-11T00:00:00Z","timestamp":1528675200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["AI123346, AI128152"],"award-info":[{"award-number":["AI123346, AI128152"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000968","name":"American Heart Association","doi-asserted-by":"publisher","award":["13GRNT16810009,13PRE16840032"],"award-info":[{"award-number":["13GRNT16810009,13PRE16840032"]}],"id":[{"id":"10.13039\/100000968","id-type":"DOI","asserted-by":"publisher"}]},{"name":"U.S. Military Infectious Diseases Research Program","award":["A1230"],"award-info":[{"award-number":["A1230"]}]},{"DOI":"10.13039\/100009238","name":"Virginia Commonwealth University","doi-asserted-by":"publisher","award":["Presidential Research Quest Fund"],"award-info":[{"award-number":["Presidential Research Quest Fund"]}],"id":[{"id":"10.13039\/100009238","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>Scrub typhus threatens one billion people in the Asia-Pacific area and cases have emerged outside this region. It is caused by infection with any of the multitude of strains of the bacterium Orientia tsutsugamushi. A vaccine that affords heterologous protection and a commercially-available molecular diagnostic assay are lacking. Herein, we determined that the nucleotide and translated amino acid sequences of outer membrane protein A (OmpA) are highly conserved among 51 O. tsutsugamushi isolates. Molecular modeling revealed the predicted tertiary structure of O. tsutsugamushi OmpA to be very similar to that of the phylogenetically-related pathogen, Anaplasma phagocytophilum, including the location of a helix that contains residues functionally essential for A. phagocytophilum infection. PCR primers were developed that amplified ompA DNA from all O. tsutsugamushi strains, but not from negative control bacteria. Using these primers in quantitative PCR enabled sensitive detection and quantitation of O. tsutsugamushi ompA DNA from organs and blood of mice that had been experimentally infected with the Karp or Gilliam strains. The high degree of OmpA conservation among O. tsutsugamushi strains evidences its potential to serve as a molecular diagnostic target and justifies its consideration as a candidate for developing a broadly-protective scrub typhus vaccine.<\/jats:p>","DOI":"10.3390\/tropicalmed3020063","type":"journal-article","created":{"date-parts":[[2018,6,11]],"date-time":"2018-06-11T11:01:01Z","timestamp":1528714861000},"page":"63","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Outer Membrane Protein A Conservation among Orientia tsutsugamushi Isolates Suggests Its Potential as a Protective Antigen and Diagnostic Target"],"prefix":"10.3390","volume":"3","author":[{"given":"Sean M.","family":"Evans","sequence":"first","affiliation":[{"name":"Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA 23298, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haley E.","family":"Adcox","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA 23298, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lauren","family":"VieBrock","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA 23298, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ryan S.","family":"Green","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA 23298, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alison","family":"Luce-Fedrow","sequence":"additional","affiliation":[{"name":"Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA"},{"name":"Department of Biology, Shippensburg University, Shippensburg, PA 17257, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Suschsmita","family":"Chattopadhyay","sequence":"additional","affiliation":[{"name":"Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ju","family":"Jiang","sequence":"additional","affiliation":[{"name":"Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Richard T.","family":"Marconi","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA 23298, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4743-5987","authenticated-orcid":false,"given":"Daniel","family":"Paris","sequence":"additional","affiliation":[{"name":"Department of Medicine, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Allen L.","family":"Richards","sequence":"additional","affiliation":[{"name":"Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD 20910, USA"},{"name":"Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jason A.","family":"Carlyon","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA 23298, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,6,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Bonell, A., Lubell, Y., Newton, P.N., Crump, J.A., and Paris, D.H. 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