Yokoyama K, Kubo T, Fujii M
Department of Chemistry, Kyushu School of Engineering, Kinki University, Fukuoka, Japan.
Nucleic Acids Symp Ser. 1999(42):169-70. doi: 10.1093/nass/42.1.169.
It was found that Gramicidin S (GS) with intramolecular antiparallel beta-sheet structure could bind to and thermally stabilize double and triple stranded DNA. UV melting study revealed that GS stabilized mixed sequence dsDNA in the presence of Mg2+ (deltaTm = +6.0) but it stabilized dsDNA with homosequence only in the absence of Mg2+. It should be pointed out that GS specifically stabilized the third strand (Hoogsteen base pair) but not double strand (Watson-Crick base pair) in triple helix DNA.
研究发现，具有分子内反平行β-折叠结构的短杆菌肽S（GS）能够结合双链和三链DNA并使其热稳定。紫外熔解研究表明，在Mg2+存在的情况下，GS能稳定混合序列双链DNA（ΔTm = +6.0），但只有在不存在Mg2+时，它才能稳定同序列双链DNA。需要指出的是，在三链螺旋DNA中，GS特异性地稳定了第三条链（Hoogsteen碱基对），而不是双链（Watson-Crick碱基对）。
