O-antigen of Vibrio cholerae O1 is controlled by ABC transporter-dependent pathway. O-antigen synthesis controlled by this pathway is initiated by a homolog of WecA, which catalyzes the transfer of GlcNAc-1-P from UDP-GlcNAc (donor) to undecaprenyl phosphate (acceptor). However, it speculates that an initial O-antigen synthesis of V. cholerae O1 is regulated by a homolog of WbaP (undecaprenyl phosphate galactose-1-phosphate tranferase). In this work, we characterized new glycosyltransferase WbeW from V. cholerae O1. Sequence and topology analyses of WbeW revealed that the protein might be a member of polyisoprenyl phosphate hexose-1-phosphate tranferase (PHPT) family. Through studies of subcellular location of His6-WbeW protein and its derivatives, which deleted with several amino acids from N-terminus, we found that the His6-WbeW protein was associated to membrane and its membrane association might be affected by diverse factors as well as α-helix transmembrane domain. The activity assay showed that the protein catalyzes the transfer of galactose-1-phosphate from UDP-Gal to undecaprenyl phosphate. This is the first report that an initial glycan of O-antigen formed by ABC-transporter-dependent pathway is galactose but not N-acetylglucosamine. This indicates that there might be a new mechanism of ABC-transporter-dependent pathway-controlled O-antigen synthesis.
저자
Chang Sup Kim [ Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 790-784 ]
Jeong Hyun Seo [ Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 790-784 ]
Hyung Joon Cha [ Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 790-784 ]
본 학회는 화학, 생화학, 분자생물학, 미생물학, 식품공학, 의학, 약학, 유전공학 및 생물공학, 환경 및 기타 공업 등 전 분야의 탄수화물관련 이론과 기술을 연구 발전시키고 산학협동을 통해 이를 보급하여 국내 관련 산업의 발전 및 국민생활의 과학화에 기여하고자 하며, 이러한 목표와 비젼의 실현을 위해 회원들이 적극적인 참여와 활동을 전개하고자 한다.