Antibacterial activities of multi drug resistant Myroides odoratimimus bacteria isolated from adult flesh flies (Diptera: Sarcophagidae) are independent of metallo beta-lactamase gene

Abstract

Flesh flies (Diptera: Sarcophagidae) are well known cause of myiasis and their gut bacteria have never been studied for antimicrobial activity against bacteria. Antimicrobial studies of Myroides spp. are restricted to nosocomial strains. A Gram-negative bacterium, Myroides sp., was isolated from the gut of adult flesh flies (Sarcophaga sp.) and submitted to evaluation of nutritional parameters using Biolog GN, 16S rRNA gene sequencing, susceptibility to various antimicrobials by disc diffusion method and detection of metallo β-lactamase genes (TUS/MUS). The antagonistic effects were tested on Gram-negative and Gram-positive bacteria isolated from human clinical specimens, environmental samples and insect mid gut. Bacterial species included were Aeromonas hydrophila, A. culicicola, Morganella morganii subsp. sibonii, Ochrobactrum anthropi, Weissella confusa, Escherichia coli, Ochrobactrum sp., Serratia sp., Kestersia sp., Ignatzschineria sp., Bacillus sp. The Myroides sp. strain was resistant to penicillin-G, erythromycin, streptomycin, amikacin, kanamycin, gentamycin, ampicillin, trimethoprim and tobramycin. These strain showed antibacterial action against all bacterial strains except W. confusa, Ignatzschineria sp., A. hydrophila and M. morganii subsp. sibonii. The multidrug resistance of the strain was similar to the resistance of clinical isolates, inhibiting growth of bacteria from clinical, environmental and insect gut samples. The metallo β-lactamase (TUS/MUS) genes were absent, and resistance due to these genes was ruled out, indicating involvement of other secretion machinery.

Infection and pathogenecity of Myroides odoratimimus (NIOCR-12) isolated from the gut of grey mullet (Mugil cephalus (Linnaeus, 1758))

“…Whereas, isolate was sensitive to antimicrobials like gatifloxacin, vancomycin, ofloxacin, sparfloxacin, azithromycin, chloramphenicol, nitrofurantoin, norfloxacin (Table 1). These antimicrobial susceptibility test results of strain NIOCR-12 agrees with that of the earlier reports of M. odoratimimus [20,21,22,23] (Table 1).…”

“…Thus, chloramphenicol may be used to distinguish the two strains of M. odoratimimus and M. odoratum. Resistance to the above mentioned antibiotics by the isolate may be due to the presence of some virulence genes or involvement of secretion machinery of multi drug efflux proteins [21]. It has also been shown that resistance to β-lactamas antibiotics is due to the production of chromosomeencoded metallo-β-lactamases (TUS-1 and MUS-1) [24].…”

A metagenomic assessment of the bacteria associated with Lucilia sericata and Lucilia cuprina (Diptera: Calliphoridae)

“…Lactobacillus is also commonly observed at decomposition sites and is known to inhibit the growth of many harmful bacteria by making environment acidic. Similarly, Myroides (Flavobacteriaceae) was present at comparatively high abundance in pupal samples, which most probably protect pupa from harmful environmental bacteria, because Myroides produces bio-surfactants with known antibacterial properties (Dharne et al 2008;Spiteller et al 2000).…”

Severe pneumonia due to an atypical organism in an immune-competent patient

“…Most strains are resistant to aminoglycosides and beta-lactams including Imipenem by the production of a chromosome-encoded metallo-beta-lactamase (TUS-1 and MUS-1) [16] . However, these strains have also demonstrated resistance independent of TUS-1 and MUS-1 [17] which warrants further investigation. The particular strain in our patient was resistant to the initial antibiotic regimen leading to his clinical deterioration.…”