Cyclic tetrapeptides from the marine strain Streptomyces sp. PNM-161a with activity against rice and yam phytopathogens
作者:Luz A. Betancur、Abel M. Forero、Adriana Romero-Otero、Lady Yohanna Sepúlveda、Nubia C. Moreno-Sarmiento、Leonardo Castellanos、Freddy A. Ramos
DOI:10.1038/s41429-019-0201-0
日期:2019.10
Two cyclotetrapeptides, henceforth named Provipeptides A (1) and B (2), along with five known diketopiperazines (3â7) were isolated from the liquid culture of marine Streptomyces sp. 161a recovered from a sample of sea grass Bryopsis sp. The structures of cyclotetrapeptides and diketopiperazines (DKPs) were established by 1D and 2D NMR data, MS, and by comparison with literature data. The absolute stereochemistry of compounds cyclo-(l-Pro-l-Leu-d-Pro-l-Phe) 1 and cyclo-(-Pro-Ile-Pro-Phe) 2 was established by the Marfeyâs method. Compound 1 showed antibacterial activity against rice phytopathogenic strains Burkholderia glumae (MICâ=â1.1âmM) and Burkholderia gladioli (MICâ=â0.068âmM), compound 2 was active only against B. glumae (MICâ=â1.1âmM), and DKP cyclo-[l-Pro-l-Leu] 5 showed to be active against B. gladioli (MICâ=â0.3âmM) and B. glumae (MICâ=â2.4âmM). Compounds 1 and 2 showed 65% and 50% inhibition of Colletotrichum gloeosporioides (yam pathogen) conidia germination, respectively at a concentration of 1.1âmM.
从海洋链霉菌(Streptomyces sp.)161a的液体培养物中分离出两种环四肽(分别命名为Provipeptides A(1)和B(2))以及五种已知的二酮哌嗪(3-7),这些物质是从海草(Bryopsis sp.)样本中提取的。通过1D和2D NMR数据、MS以及与文献数据的比较,确定了环四肽和二酮哌嗪(DKP)的结构。通过马菲氏(Marfey’s)法确定了化合物cyclo-(l-Pro-l-Leu-d-Pro-l-Phe) 1和cyclo-(-Pro-Ile-Pro-Phe) 2的绝对立体化学。化合物1对水稻病原菌Burkholderia glumae(MIC≒1.1≒mM)和Burkholderia gladioli(MIC≒0.068≒mM)具有抗菌活性,化合物2仅对B. glumae(MIC≒1.1≒mM)具有活性,而DKP cyclo-[l-Pro-l-Leu] 5对B. gladioli(MIC≒0.3≒mM)和B. glumae(MIC≒