Effect of DNA binding protein Ssh12 from hyperthermophilic archaeon Sulfolobus shibatae on DNA supercoiling  

作　　者：楼慧强 黄力 VietQ.Mai 

机构地区：[1]Pomona College, CA 91711

出　　处：《Science China(Life Sciences)》1999年第4期401-408,共8页中国科学（生命科学英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant No. 39770006);the Irvine Foundation and the Director's fund in the Institute of Microbiology;the Chinese Academy of Sciences, and a Grant-in-Aid for Scientists Returning f

摘　　要：An 11.5-ku DNA binding protein, designated as Sshl2, was purified from the hyperthermophilic archaeon Sulfolobus shibatae by column chromatography in SP Sepharose, DNA cellulose and phosphocellulose. Sshl2 accounts for about 4 % of the total cellular protein. The protein is capable of binding to both negatively supercoiled and relaxed DNAs. Nick closure analysis revealed that Sshl2 constrains negative supercoils upon binding to DNA. While the ability of the protein to constrain supercoils is weak at 22℃ , it is enhanced substantially at temperatures higher than 37℃ . Both the cellular content and supercoil-constraining ability of Sshl2 suggest that the protein may play an important role in the organization and stabilization of the chromosome of S. shibatae.An 11.5-ku DNA binding protein, designated as Sshl2, was purified from the hyperthermophilic archaeon Sulfolobus shibatae by column chromatography in SP Sepharose, DNA cellulose and phosphocellulose. Sshl2 accounts for about 4 % of the total cellular protein. The protein is capable of binding to both negatively supercoiled and relaxed DNAs. Nick closure analysis revealed that Sshl2 constrains negative supercoils upon binding to DNA. While the ability of the protein to constrain supercoils is weak at 22℃ , it is enhanced substantially at temperatures higher than 37℃ . Both the cellular content and supercoil-constraining ability of Sshl2 suggest that the protein may play an important role in the organization and stabilization of the chromosome of S. shibatae.

关 键 词：HYPERTHERMOPHILIC ARCHAEA SULFOLOBUS shibatae DNA BINDING PROTEIN supercoiling. 

分 类 号：Q523[生物学—生物化学]