Crop Research Institute, Drnovska 507/73, CZ-161 06, Prague 6-Ruzyne, Czechia.
Faculty of Agrobiology, Food and Natural Resources, Department of Microbiology, Nutrition and Dietetics, Czech University of Life Sciences, Kamycka 129, CZ-165 21, Prague 6-Suchdol, Czechia.
Microb Ecol. 2021 Feb;81(2):506-522. doi: 10.1007/s00248-020-01581-y. Epub 2020 Aug 27.
Arthropod-associated microorganisms are important because they affect host fitness, protect hosts from pathogens, and influence the host's ability to vector pathogens. Stored product mites (Astigmata) often establish large populations in various types of food items, damaging the food by direct feeding and introducing contaminants, including their own bodies, allergen-containing feces, and associated microorganisms. Here we access the microbial structure and abundance in rearing diets, eggs, feces fraction, and mite bodies of 16 mite populations belonging to three species (Carpoglyphus lactis, Acarus siro, and Tyrophagus putrescentiae) using quantitative PCR and 16S ribosomal RNA (rRNA) gene amplicon sequencing. The mite microbiomes had a complex structure dominated by the following bacterial taxa (OTUs): (a) intracellular symbionts of the genera Cardinium and Wolbachia in the mite bodies and eggs; (b) putative gut symbionts of the genera Solitalea, Bartonella, and Sodalis abundant in mite bodies and also present in mite feces; (c) feces-associated or environmental bacteria of the genera Bacillus, Staphylococcus, and Kocuria in the diet, mite bodies, and feces. Interestingly and counterintuitively, the differences between microbial communities in various conspecific mite populations were higher than those between different mite species. To explain some of these differences, we hypothesize that the intracellular bacterial symbionts can affect microbiome composition in mite bodies, causing differences between microbial profiles. Microbial profiles differed between various sample types, such as mite eggs, bodies, and the environment (spent growth medium-SPGM). Low bacterial abundances in eggs may result in stochastic effects in parent-offspring microbial transmission, except for the intracellular symbionts. Bacteria in the rearing diet had little effect on the microbial community structure in SPGM and mite bodies. Mite fitness was positively correlated with bacterial abundance in SPGM and negatively correlated with bacterial abundances in mite bodies. Our study demonstrates critical host-microbe interactions, affecting all stages of mite growth and leading to alteration of the environmental microbiome. Correlational evidence based on absolute quantitation of bacterial 16S rRNA gene copies suggests that mite-associated microorganisms are critical for modulating important pest properties of mites by altering population growth.
节肢动物相关微生物很重要，因为它们会影响宿主的健康状况，保护宿主免受病原体侵害，并影响宿主传播病原体的能力。储存产品螨（Astigmata）经常在各种类型的食物中建立大量种群，通过直接进食和引入包括自身身体、含过敏原的粪便以及相关微生物在内的污染物来破坏食物。在这里，我们使用定量 PCR 和 16S 核糖体 RNA (rRNA) 基因扩增子测序来访问属于三个物种（乳糜果糖螨、虹彩螨和腐败酪螨）的 16 个螨种群的饲养饮食、卵、粪便部分和螨体中的微生物结构和丰度。螨类微生物组结构复杂，主要由以下细菌分类群（OTUs）组成：（a）螨体和卵中的卡氏菌属和沃尔巴克氏体属的细胞内共生体；（b）在螨体中丰富的假定肠道共生菌 Solitalea、Bartonella 和 Sodalis，也存在于螨粪便中；（c）在饮食、螨体和粪便中属于芽孢杆菌属、葡萄球菌属和柯克氏菌属的粪便相关或环境细菌。有趣的是，与不同螨种相比，同种螨种群中微生物群落之间的差异更高。为了解释其中的一些差异，我们假设细胞内细菌共生体可以影响螨体中的微生物组组成，从而导致微生物图谱之间的差异。各种样本类型（如螨卵、螨体和环境（用过的生长培养基-SPGM））之间的微生物图谱不同。卵中细菌丰度低可能导致亲代-后代微生物传播中的随机效应，细胞内共生体除外。饲养饮食中的细菌对 SPGM 和螨体中的微生物群落结构几乎没有影响。螨的适应性与 SPGM 和螨体中的细菌丰度呈正相关。我们的研究表明了关键的宿主-微生物相互作用，这些相互作用影响螨生长的各个阶段，并导致环境微生物组的改变。基于细菌 16S rRNA 基因拷贝数的绝对定量的相关证据表明，螨相关微生物通过改变种群生长对调节螨的重要害虫特性至关重要。
