Insights into the bacterial symbiont diversity in spiders

Abstract

Most spiders are natural enemies of pests, and it is beneficial for the biological control of pests to learn the relationships between symbionts and their spider hosts. Research on the bacterial communities of insects has been conducted recently, but only a few studies have addressed the bacterial communities of spiders. To obtain a complete overview of the microbial communities of spiders, we examined eight species of spider (Pirata subpiraticus, Agelena difficilis, Artema atlanta, Nurscia albofasciata, Agelena labyrinthica, Ummeliata insecticeps, Dictis striatipes, and Hylyphantes graminicola) with high‐throughput sequencing based on the V3 and V4 regions of the 16S rRNA gene. The bacterial communities of the spider samples were dominated by five types of endosymbionts, Wolbachia, Cardinium, Rickettsia, Spiroplasma, and Rickettsiella. The dominant OTUs (operational taxonomic units) from each of the five endosymbionts were analyzed, and the results showed that different spider species were usually dominated by special OTUs. In addition to endosymbionts, Pseudomonas, Sphingomonas, Acinetobacter, Novosphingobium, Aquabacterium, Methylobacterium, Brevundimonas, Rhizobium, Bradyrhizobium, Citrobacter, Arthrobacter, Pseudonocardia, Microbacterium, Lactobacillus, and Lactococcus were detected in spider samples in our study. Moreover, the abundance of Sphingomonas, Methylobacterium, Brevundimonas, and Rhizobium in the spider D. striatipes was significantly higher (p < .05) than the bacterial abundance of these species in seven other spider species. These findings suggest that same as in insects, co‐infection of multiple types of endosymbionts is common in the hosts of the Araneae order, and other bacterial taxa also exist in spiders besides the endosymbionts.

Taking insight into the gut microbiota of three spider species: No characteristic symbiont was found corresponding to the special feeding style of spiders

“…Wolbachia and Rickettsiella are endosymbionts existing in spider hosts (Duron, Bouchon, et al, ; Goodacre et al, ), and the relative abundance of these endosymbionts varies between spider hosts (Zhang et al, ). In this study, the relative abundance of Wolbachia and Rickettsiella in N .…”

“…Wolbachia and Rickettsiella are endosymbionts existing in spider hosts (Duron, Bouchon, et al, 2008;Goodacre et al, 2006), and the relative abundance of these endosymbionts varies between spider hosts (Zhang et al, 2018). In this study, the relative abundance of Wolbachia and Rickettsiella in N. albofasciata (spinning spider) was significantly higher than that in P. laura (without web) and P. astrigera (without web) Endosymbionts are widely distributed in the organs and tissues of their arthropod hosts (Pietri, DeBruhl, & Sullivan, 2016;Sicard, Dittmer, Grève, Bouchon, & Braquart-Varnier, 2014), and whether the high abundance distribution of endosymbionts in the intestinal tissues correlates with the hosts' digestive function and immune defense is interesting.…”

“…Most of the studies on microorganisms within spiders have focused on endosymbionts and their reproductive effects on their hosts (Duron, Hurst, Hornett, Josling, & Engelstädter, 2008;Goodacre, Martin, Thomas, & Hewitt, 2006;Rowley, Raven, & McGraw, 2004). Endosymbionts (such as Wolbachia, Cardinium, Spiroplasma, and Rickettsia) prevail in some spider hosts, and some of them have a great effect on spider reproduction by inducing sex ratio variations (Gunnarsson, Goodacre, & Hewitt, 2009;Vanthournout & Hendrickx, 2015;Vanthournout, Swaegers, & Hendrickx, 2011;Vanthournout, Vandomme, & Hendrickx, 2014;Zhang, Yun, Hu, & Peng, 2018). Although much research has been conducted on endosymbionts in spiders, gut bacteria, as a very important part of bacterial communities in spiders, have rarely been reported on.…”

Are you what you eat? A highly transient and prey‐influenced gut microbiome in the grey house spider Badumna longinqua

“…Also, spiders often feed irregularly, leading to pronounced environmental fluctuations in their gut lumen, which could encumber the establishment of a stable microbiome (Vanthournout & Hendrickx, ). However, recent work suggests the presence of typical insect gut microbial taxa in the digestive tract of spiders (Zhang, Yun, Hu, & Peng, ), possibly resulting from a temporary recruitment of prey‐derived taxa. Considering this background, we expect that the spiders lack a stable core microbiome and instead possess a highly transient microbiome, whose assembly is dictated by dietary influences.…”

Endosymbiotic Rickettsiella causes cytoplasmic incompatibility in a spider host

“…Maternally transmitted endosymbiotic bacteria are common in arthropods, and are 35 estimated to infect nearly half of all arthropod species [1][2][3][4]. These inherited endosymbionts 36 frequently manipulate host reproduction to promote symbiont transmission and spread in the host 37 population [5].…”