Hansen J, Pschorn W, Ristow H
Eur J Biochem. 1982 Aug;126(2):279-84. doi: 10.1111/j.1432-1033.1982.tb06776.x.
The peptide antibiotic tyrocidine which is produced by Bacillus brevis and is probably involved in sporogenesis, unwinds superhelical plasmids in vitro at low peptide: DNA ratios, as found by gel electrophoresis. At higher peptide concentrations, the DNA is packed tightly leading to apparent nuclease stability of the complex and inhibition of RNA synthesis. The addition of the linear gramicidin, another peptide antibiotic synthesized by the same bacterial strain, partially restores transcription by breaking down the tightly packed DNA X peptide complex. The complexed DNA, after nuclease digestion, is retained on a nitrocellulose filter, but loses its affinity for the filter in the presence of gramicidin. The results are discussed with respect to possible functions of the two peptides within in the cell.
短杆菌肽是由短短芽孢杆菌产生的一种肽抗生素，可能参与孢子形成过程。凝胶电泳结果表明，在低肽与DNA比例下，短杆菌肽能在体外解开超螺旋质粒。在较高肽浓度时，DNA紧密堆积，导致复合物具有明显的核酸酶稳定性，并抑制RNA合成。加入同样由该菌株合成的线性短杆菌肽，可通过分解紧密堆积的DNA-肽复合物部分恢复转录。经核酸酶消化后，复合DNA保留在硝酸纤维素滤膜上，但在短杆菌肽存在时会失去对滤膜的亲和力。文中针对这两种肽在细胞内可能的功能进行了讨论。
