辣木(或奇迹树)是一种因其种子荚和叶子而广泛种植的野生植物,用于传统草药。宏基因组全基因组鸟枪测序(mWGS)方法用于表征该野生植物根瘤菌和周围散装土壤微生物组的抗生素抗性基因(ARGs),并找出高丰度ARGs的机会和后果,例如,mtrA,gls,SoxR,oleC,nova,kdpE,vanRO,pary,和rbpa,通过移动遗传元件(MGEs)水平转移到人类肠道病原体。结果表明,这些ARGs的丰度,除了gls,油菌的根际高于散装土壤微生物组,在两种土壤类型中均没有出现新的土壤ARG的迹象。以前在门放线菌成员中检测到最丰富的ARGs的最丰富的代谢过程,变形杆菌,酸杆菌,氯氟菌,和Firmicutes。这些过程涉及三种抗性机制,即抗生素外排泵,抗生素靶标改变和抗生素靶标保护。抗生素外排机制包括抗性-结瘤-细胞分裂(RND),ATP结合盒(ABC),和主要促进剂超家族(MFS)抗生素泵以及两组分调节kdpDE系统。抗生素靶标改变包括糖肽抗性基因簇(vanRO),氨基香豆素抗性parY,和氨基香豆素自抗性parY。同时,抗生素靶标保护机制包括RbpA细菌RNA聚合酶(rpoB)结合蛋白。该研究支持了这些ARGs可能水平转移到人类肠道以及新的多药耐药临床分离株的出现。因此,特别是对于人类营养行业或传统医学领域使用的植物,需要谨慎的农业实践。
Moringa oleifera (or the miracle tree) is a wild plant species widely grown for its seed pods and leaves, and is used in traditional herbal medicine. The metagenomic whole genome shotgun sequencing (mWGS) approach was used to characterize antibiotic resistance genes (ARGs) of the rhizobiomes of this wild plant and surrounding bulk soil microbiomes and to figure out the chance and consequences for highly abundant ARGs, e.g., mtrA, golS, soxR, oleC, novA, kdpE, vanRO, parY, and rbpA, to horizontally transfer to human gut pathogens via mobile genetic elements (MGEs). The results indicated that abundance of these ARGs, except for golS, was higher in rhizosphere of M. oleifera than that in bulk soil microbiome with no signs of emerging new soil ARGs in either soil type. The most highly abundant metabolic processes of the most abundant ARGs were previously detected in members of phyla Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, and Firmicutes. These processes refer to three resistance mechanisms namely antibiotic efflux pump, antibiotic target alteration and antibiotic target protection. Antibiotic efflux mechanism included resistance-nodulation-cell division (RND), ATP-binding cassette (ABC), and major facilitator superfamily (MFS) antibiotics pumps as well as the two-component regulatory kdpDE system. Antibiotic target alteration included glycopeptide resistance gene cluster (vanRO), aminocoumarin resistance parY, and aminocoumarin self-resistance parY. While, antibiotic target protection mechanism included RbpA bacterial RNA polymerase (rpoB)-binding protein. The study supports the claim of the possible horizontal transfer of these ARGs to human gut and emergence of new multidrug resistant clinical isolates. Thus, careful agricultural practices are required especially for plants used in circles of human nutrition industry or in traditional medicine.