http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Peggion, Cristina (검색결과 1 건)
- 무료
- 기관 내 무료
- 유료
-
Trichogin GA IV: A versatile template for the synthesis of novel peptaibiotics
Zotti, Marta De,Biondi, Barbara,Peggion, Cristina,Formaggio, Fernando,Park, Yoonkyung,Hahm, Kyung-Soo,Toniolo, Claudio The Royal Society of Chemistry 2012 Organic & biomolecular chemistry Vol.10 No.6
<P>Trichogin GA IV, isolated from the fungus <I>Trichoderma longibrachiatum</I>, is the prototype of lipopeptaibols, the sub-class of short-length peptaibiotics exhibiting membrane-modifying properties. This peptaibol is predominantly folded in a mixed 3<SUB>10</SUB>-/α- helical conformation with a clear, albeit modest, amphiphilic character, which is likely to be responsible for its capability to perturb bacterial membranes and to induce cell death. In previous papers, we reported on the interesting biological properties of trichogin GA IV, namely its good activity against Gram positive bacteria, in particular methicillin-resistant <I>S. aureus</I> strains, its stability towards proteolytic degradation, and its low hemolytic activity. Aiming at broadening the antimicrobial activity spectrum by increasing the peptide helical amphiphilicity, in this work we synthesized, by solution and solid-phase methodologies, purified and fully characterized a set of trichogin GA IV analogs in which the four Gly residues at positions 2, 5, 6, 9, lying in the poorly hydrophilic face of the helical structure, are substituted by one (position 2, 5, 6 or 9), two (positions 5 and 6), three (positions 2, 5, and 9), and four (positions 2, 5, 6, and 9) Lys residues. The conformational preferences of the Lys-containing analogs were assessed by FT-IR absorption, CD and 2D-NMR techniques in aqueous, organic, and membrane-mimetic environments. Interestingly, it turns out that the presence of charged residues induces a transition of the helical conformation adopted by the peptaibols (from 3<SUB>10</SUB>- to α-helix) as a function of pH in a reversible process. The role played in the analogs by the markedly increased amphiphilicity was further tested by fluorescence leakage experiments in model membranes, protease resistance, antibacterial and antifungal activities, cytotoxicity, and hemolysis. Taken together, our biological results provide evidence that some of the least substituted among these analogs are good candidates for the development of new membrane-active antimicrobial agents.</P> <P>Graphic Abstract</P><P>One or more Gly-to-Lys replacements on the hydrophilic face of the peptide-template trichogin GA IV modulate its biological properties and promote a pH-mediated, reversible, 3<SUB>10</SUB>- to α-helix transition. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c1ob06178j'> </P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
