Distamycin and penta-N-methylpyrrolecarboxamide binding sites on native DNA. A comparison of methidiumpropyl-EDTA-Fe(II) footprinting and DNA affinity cleaving.
Distamycin and penta-N-methylpyrrolecarboxamide binding sites on native DNA. A comparison of methidiumpropyl-EDTA-Fe(II) footprinting and DNA affinity cleaving.
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DOI：
10.1080/07391102.1984.10507508
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发表时间：
1984-03
影响因子：
4.4
通讯作者：
P. Schultz;P. Dervan
中科院分区：
文献类型：
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作者：
P. Schultz;P. Dervan
我们用两种直接方法研究了pBR322质粒的三个DNA限制性片段上的二霉素和五- n -甲基吡咯甲酰胺的结合位置和位点大小。我们发现甲巯丙基edta。铁（II）足迹和DNA亲和切割方法报告了与异质DNA结合的三肽和五肽的共同结合位置和位点大小。三肽distamycin结合5碱基对位点，优先选择poly（dA）。保利(dT)地区。该五肽结合6-7个碱基对位点，具有聚（dA）的偏好。保利(dT)地区。这些结果与distamycin与4个羧基酰胺N-H的氢键5个A + T碱基对以等几何螺旋形式结合在DNA的小凹槽上的观点一致。这些数据支持一个模型，即每个羧基酰胺的N- h可以与两个碱基形成氢键，一个是胸腺嘧啶的O(2)，一个是腺嘌呤的N(3)，它们位于螺旋的相反链上相邻的碱基对上。在大多数（但不是全部）情况下，三肽和五肽可以在每个富含A + T的结合位点上采用两种取向。
Using two direct methods we have studied the binding locations and site sizes of distamycin and penta-N-methylpyrrolecarboxamide on three DNA restriction fragments from pBR322 plasmid. We find that methidiumpropyl-EDTA.Fe(II) footprinting and DNA affinity cleaving methods report common binding locations and site sizes for the tri- and pentapeptides bound to heterogeneous DNA. The tripeptide distamycin binds 5-base-pair sites with a preference for poly(dA).poly(dT) regions. The pentapeptide binds 6-7-base-pair sites with a preference for poly(dA).poly(dT) regions. These results are consistent with distamycin binding as an isogeometric helix to the minor groove of DNA with the four carboxamide N-H's hydrogen bonding five A + T base pairs. The data supports a model where each of the carboxamide N-H's can hydrogen bond to two bases, either O(2) of thymine or N(3) of adenine, located on adjacent base pairs on opposite strands of the helix. In most (but not all) cases the tri- and pentapeptide can adopt two orientations at each A + T rich binding site.