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Abstract
Scrub typhus is an acute, febrile illness caused by Orientia tsutsugamushi infection and it is one of the main causes of acute febrile illness in the Asian-Pacific region. The incidence of scrub typhus has been significantly increased in Korea during last 10 years. Although early diagnosis and proper antibiotic treatment are important to prevent severe complications, the clinical discrimination of scrub typhus from other undifferentiated fevers, such as leptospirosis or dengue fever, is often very difficult. In addition, an effective vaccine has not yet been developed. As a novel diagnostic and vaccine target for scrub typhus, we described surface cell antigen (sca) family genes encoding autotransporter proteins found in the genome of O. tsutsugamushi. The molecular characteristics and recent findings on the bacterial genes were introduced in this letter.
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Figure 1.
(A) Schematic diagram of O. tsutsugamushi autotransporter proteins. Schematic presentation of the five Sca proteins identified in the genome of the O. tsutsugamushi Boryong strain. The domain structures were predicted using SMART (Simple Modular Architecture Research Tool; http://smart.embl-heidelberg.de/). (B) 3D Structure model of the autotransporter proteins predicted by I-TASSER program (http://zhanglab.ccmb.med.umich.edu/I-TASSER/).
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