The gut bacterial communities across six grasshopper species from a coastal tallgrass prairie

Abstract

Insect microbiomes play an important role in the health and fitness of insect hosts by contributing to nutrient absorption, immune health, and overall ecological fitness. As such, research interests in insect microbiomes have focused on agriculturally and industrially important organisms such as honey bees and termites. Orthopterans, on the other hand, have not been well explored for their resident microbial communities. Grasshoppers are an integral part of grassland ecosystems and provide important ecosystem services. Conversely, grasshoppers can be an agricultural pest requiring management with broad spectrum pesticides. However, little is known about the microbiomes of grasshoppers and their potential contribution to grasshopper biology. Here we examine the gut microbiome of six species of grasshoppers (n = 60) from a coastal tallgrass prairie ecosystem to gain a better understanding of the microbial communities present across the orthopteran order in this ecosystem. We found that there are bacterial phyla common to all six grasshopper species: Actinobacteria, Proteobacteria, Firmicutes, and to a lesser degree, Tenericutes. Although the grasshopper species shared a high relative abundance of these groups, there were notable shifts in dominant phyla depending on the grasshopper species. Moreover, measures of alpha diversity revealed a more diverse microbiome in males than females. Our observations support the hypothesis that there is a "core" group of bacterial families in these grasshopper species and factors such as trophic behaviors and the evolution of the host may contribute to the shifts in prevalence among these core microbial groups. OPEN ACCESSCitation: Muratore M, Prather C, Sun Y (2020) The gut bacterial communities across six grasshopper species from a coastal tallgrass prairie. PLoS ONE 15(1): e0228406. https://doi.org/10.

Environmental Nutrients Alter Bacterial and Fungal Gut Microbiomes in the Common Meadow Katydid, Orchelimum vulgare

“…The flexible feeding behavior might affect the composition of the gut microbiome, which can further impact the animal's fitness and functions. While our earlier work identified a "core" bacterial community in the gut of O. vulgare (Muratore et al, 2020), whether the microbiome composition of O. vulgare can be modulated by environmental nutrient conditions has not been determined.…”

“…A detailed description of this procedure was explained elsewhere (Muratore et al, 2020). Briefly, frozen O. vulgare gut samples were homogenized into smaller pieces for DNA extraction using the Qiagen DNeasy Blood and Tissue Kit (Qiagen 69504) following the manufacturer's protocol.…”

“…As explained in a previous publication (Muratore et al, 2020), high throughput DNA sequencing was performed by Zymo Research (Irvine, CA). Before the library construction took place, extracted DNA was quantified using nanodrop and the 2100 Bioanalyzer System (Agilent).…”

“…Our previous work has indicated that O. vulgare, when compared to other related grasshoppers, contains characteristic bacterial communities that may depend on diet or evolutionary lineage (Muratore et al, 2020). While almost nothing is known about the mode of transmission for bacterial communities in O. vulgare, it can be assumed that some of these resident bacteria come from diet, environmental contact, and feeding behaviors (Billiet et al, 2016;Krams et al, 2017).…”

“…Conversely, behaviors of the insect host like feeding and social roles can be reflected in variations in their microbiome (Yun et al, 2014;Jones et al, 2018;Kakumanu et al, 2018;Obadia et al, 2018). Recently, we demonstrated that orthopterans, specifically katydids and grasshoppers, share a characteristic bacterial community dominated by Proteobacteria, Firmicutes, and Actinobacteria (Muratore et al, 2020). Because these organisms were collected from a coastal prairie under a fully factorial fertilization experiment, we had a unique opportunity to further dissect how the microbial community composition responds to nutrient modifications in the environment.…”