Detection and Characterization of Streptomycin Resistance (strA-strB) in a Honeybee Gut Symbiont (Snodgrassella alvi) and the Associated Risk of Antibiotic Resistance Transfer

Abstract

Use of antibiotics in medicine and farming contributes to increasing numbers of antibiotic-resistant bacteria in diverse environments. The ability of antibiotic resistance genes (ARG) to transfer between bacteria genera contributes to this spread. It is difficult to directly link antibiotic exposure to the spread of ARG in a natural environment where environmental settings and study populations cannot be fully controlled. We used managed honeybees in environments with contrasting streptomycin exposure (USA: high exposure, Norway: low exposure) and mapped the prevalence and spread of transferrable streptomycin resistance genes. We found a high prevalence of strA-strB genes in the USA compared to Norway with 17/90 and 1/90 positive samples, respectively (p < 0.00007). We identified strA-strB genes on a transferrable transposon Tn5393 in the honeybee gut symbiont Snodgrassella alvi. Such transfer of resistance genes increases the risk of the spread to new environments as honeybees are moved to new pollination sites.

Diversity and functional analysis of Chinese bumblebee gut microbiota reveal the metabolic niche and antibiotic resistance variation of Gilliamella

“…Treatment with antibiotics can be a strong selective force in the microbiota of bees (Kwong & Moran, 2016). Previous observations on honeybee gut microbiota reveal that long‐term antibiotic treatment affects the distribution of ARGs in bacteria, and it is subject to the management policies in different countries (Ludvigsen et al ., 2017; Ludvigsen et al ., 2018). In the USA, oxytetracycline is widely used for the control of larval pathogens in commercial beekeeping (Reybroeck et al ., 2012), and tetracycline‐resistant genes have been widely detected in the gut microbiota from domestic honeybee colonies in the USA (Tian et al ., 2012).…”

Antibiotic resistant bacteria and commensal fungi are common and conserved in the mosquito microbiome

“…The majority of research investigating the capacity of insects to harbor antibiotic resistant bacteria has focused on flies and their potential role as vectors to transport antibiotic resistant bacteria from animal production facilities to human populations [31–34]. Additionally, honeybee and various plant feeding insects have also been found to carry antibiotic resistant bacteria [35,36]. Here we show that antibiotic resistant bacteria, including multiple-antibiotic resistant isolates, are commonly recovered from colony-reared and wild-caught mosquitoes, across three different mosquito genera.…”

Honey bees as models for gut microbiota research

“…This practice has resulted in high frequencies of antibiotic resistance determinants in core gut bacteria isolated from bees in the United States, in contrast to gut bacteria of honey bees from countries which do not permit the use of antibiotics in beekeeping 116,117 . In both human and honey bee gut communities, resistance determinants have been exchanged among community members through horizontal transfer 118 . Furthermore, antibiotic exposure has an immediate impact on the size and diversity of honey bee gut communities 12,90 .…”