Department of Microbiology, Stellenbosch University, Stellenbosch, 7600, South Africa.
Probiotics Antimicrob Proteins. 2020 Dec;12(4):1310-1320. doi: 10.1007/s12602-020-09688-x.
The over-prescription of antibiotics for treatment of infections is primarily to blame for the increase in bacterial resistance. Added to the problem is the slow rate at which novel antibiotics are discovered and the many processes that need to be followed to classify antimicrobials safe for medical use. Xenorhabdus spp. of the family Enterobacteriaceae, mutualistically associated with entomopathogenic nematodes of the genus Steinernema, produce a variety of antibacterial peptides, including bacteriocins, depsipeptides, xenocoumacins and PAX (peptide antimicrobial-Xenorhabdus) peptides, plus additional secondary metabolites with antibacterial and antifungal activity. The secondary metabolites of some strains are active against protozoa and a few have anti-carcinogenic properties. It is thus not surprising that nematodes invaded by a single strain of a Xenorhabdus species are not infected by other microorganisms. In this review, the antimicrobial compounds produced by Xenorhabdus spp. are listed and the gene clusters involved in synthesis of these secondary metabolites are discussed. We also review growth conditions required for increased production of antimicrobial compounds.
抗生素的过度处方用于治疗感染是导致细菌耐药性增加的主要原因。此外，新型抗生素的发现速度缓慢，并且需要遵循许多程序来将可用于医疗用途的抗菌药物进行分类。肠杆菌科的 Xenorhabdus 属与食虫性线虫属 Steinernema 互利共生，产生多种抗菌肽，包括细菌素、环二肽、异环肽和 PAX（肽抗菌-Xenorhabdus）肽，以及具有抗菌和抗真菌活性的其他次生代谢物。一些菌株的次生代谢物对原生动物具有活性，少数具有抗癌特性。因此，被单一 Xenorhabdus 物种的线虫入侵的线虫不会被其他微生物感染也就不足为奇了。在这篇综述中，列出了 Xenorhabdus 属产生的抗菌化合物，并讨论了参与这些次生代谢物合成的基因簇。我们还回顾了增加抗菌化合物产量所需的生长条件。
