發(fā)布者：抗性基因網(wǎng) 時(shí)間：2023-06-12 瀏覽量：400
摘要
? ? ? 在作為環(huán)境宿主的水生細(xì)菌中，耐藥性和毒力的共同出現(xiàn)往往被忽視，而這些特征向具有臨床意義的菌株的傳播在未來(lái)會(huì)帶來(lái)不可預(yù)見(jiàn)的問(wèn)題。在這項(xiàng)調(diào)查中，同時(shí)從多種水生棲息地（即地下水、運(yùn)河、河流和沿海水域）鑒定的環(huán)境細(xì)菌的抗生素耐藥性、金屬耐受性、毒力因子和編碼這些決定因素的基因進(jìn)行了分析。來(lái)自污染河流和運(yùn)河的菌株表現(xiàn)出更高的耐藥性和毒力，尤其是格氏假單胞菌和熒光假單胞菌對(duì)堿性蛋白酶和磷脂酶的產(chǎn)生表現(xiàn)出較高的抗生素耐藥性指數(shù)（ARI>0.6–0.8）。機(jī)會(huì)性病原體，包括副溶血性弧菌、溶藻弧菌、創(chuàng)傷弧菌、棒狀桿菌和testosteroni Comamonas，表達(dá)了所有三種毒力因子，但抗性相對(duì)較低。然而，創(chuàng)傷弧菌和溶藻弧菌表現(xiàn)出多類(lèi)抗生素耐藥性（5/6類(lèi)）。宏基因組分析顯示，淡水中與β-內(nèi)酰胺耐藥性相對(duì)應(yīng)的基因顯著高于海水（p<0.05），而海水中的多藥耐藥性基因更高（p<0.05）。在所有水體中，大量的毒力基因?qū)儆诜置谙到y(tǒng)蛋白，其次是運(yùn)動(dòng)相關(guān)基因。可培養(yǎng)細(xì)菌顯示，31個(gè)靶向基因與表達(dá)的抗性和毒力之間存在正相關(guān)和負(fù)相關(guān)的差異分布。在不動(dòng)桿菌中，磷脂酶的產(chǎn)生、其他毒力基因（OVG）和對(duì)DNA合成抑制劑（DSI）的抗性之間存在顯著的正相關(guān)。在假單胞菌中，毒素基因（toxA、eta、hlyA和stx）與細(xì)胞壁合成抑制劑抗性（CSI）以及OVG和粘附基因（eae、afa、papC和papA）呈正相關(guān)。網(wǎng)絡(luò)分析顯示，非病原體主導(dǎo)的基因ncc、arsB、strA、merA和intI的獨(dú)特聚類(lèi)，以及弧菌主導(dǎo)的基因pho、erm、nfsA、trh、lasB、tdh和invA的獨(dú)特聚類(lèi)。這項(xiàng)研究擴(kuò)展了對(duì)水生水庫(kù)細(xì)菌共同發(fā)生的耐藥性和毒力的認(rèn)識(shí)，這些細(xì)菌可能在未來(lái)對(duì)公眾健康構(gòu)成嚴(yán)重威脅。
Abstract
Co-occurrence of resistance and virulence is often overlooked in aquatic bacteria as environmental reservoirs, while transmission of these characteristics to clinically significant strains present unforeseen problems in future. In this investigation, environmental bacteria identified concurrently from multiple aquatic habitats viz., groundwater, canal, river and coastal waters were profiled for antibiotic resistance, metal tolerance, virulence factors and genes coding for these determinants. Strains from polluted river and canal exhibited higher resistance and virulence, especially Pseudomonas gessardii and P. fluorescens displayed high antibiotic resistance index (ARI > 0.6–0.8) with Alkaline Protease and Phospholipase production. Opportunistic pathogens including Vibrio parahaemolyticus, V. alginolyticus, V. vulnificus, Corynebacterium and Comamonas testosteroni expressed all three virulence factors with relatively low resistance. However, V. vulnificus and V. alginolyticus exhibited multiclass antibiotic resistance (5/6 classes). Metagenomic analysis revealed that genes corresponding to beta-lactam resistance were significantly higher (p < 0.05) in freshwater than seawater, while multidrug resistance gene were higher (p < 0.05) in seawater. In all aquatic bodies, abundant virulence genes belonged to secretion system proteins followed by motility related genes. Culturable bacteria revealed differential distribution of positive and negative correlation between 31 targeted genes with expressed resistance and virulence. Among Acinetobacter, significant positive correlation was found between Phospholipase production, other virulence genes (OVGs) and resistance to DNA Synthesis Inhibitors (DSI). In Pseudomonas, positive correlation was detected between toxin genes (toxA, eta, hlyA and stx) and resistance to cell wall synthesis inhibitors (CSI) as well as with OVGs and adhesion genes (eae, afa, papC and papA). Network analysis displayed unique clustering of genes ncc, arsB, strA, merA and intI dominated by non-pathogens and distinct clustering of genes pho, erm, nfsA, trh, lasB, tdh and invA by Vibrio. This investigation extends insight on co-occurring resistance and virulence in aquatic reservoir bacteria that could pose serious threats to public health in future.
https://www.sciencedirect.com/science/article/abs/pii/S0048969722063203