Enterococci isolated from farm ostriches and their relation to enterocins

Enterocin M in Interaction in Broiler Rabbits with Autochthonous, Biofilm-Forming Enterococcus hirae Kr8 Strain

Young rabbits are susceptible to gastrointestinal diseases caused by bacteria. Enterococcus hirae can be associated with diseases. But enterocins produced by some enterococcal species can prevent/reduce this problem. Therefore, the interaction of enterocin M with a biofilm-forming, autochthonous E. hirae Kr8⁺ strain was tested in rabbits to assess enterocin potential in vivo. Rabbits (96), aged 35 days, both sexes, meat line M91 breed were divided into four groups, control C and three experimental groups. The rabbits in C received the standard diet, rabbits in experimental group 1 (E1) received 10⁸ CFU/mL of Kr8⁺, a dose 500 µL/animal/day, E2 received Ent M (50 µL/animal/day), and E3 received both Kr8⁺ and Ent M in their drinking water over 21 days. The experiment lasted 42 days. Feces and blood were sampled at day 0/1 (at the start of the experiment, fecal mixture of 96 animals, n = 10), at day 21 (five fecal mixtures per group, n = 5), and at day 42 (21 days after additives cessation, the same). At days 21 and 42, four rabbits from each group were slaughtered, and cecum and appendix were sampled for standard microbial analysis. Ent M showed decreased tendency of Kr8⁺. Using next-generation sequencing, the phyla detected with the highest abundance were Firmicutes, Verrucomicrobia, Bacteroidetes, Tenericutes, Proteobacteria, Cyanobacteria, Saccharibacteria, and Actinobacteria. Interaction of Ent M with some phyla resulted in reduced abundance percentage. At day 21, significantly increased phagocytic activity (PA) was found in E1 and E2 (p < 0.001). Kr8⁺ did not attack PA and did not stimulate oxidative stress. But Ent M supported PA. The prospective importance of this study lies in beneficial interaction of enterocin in host body.

Enterococcal Species Associated with Slovak Raw Goat Milk, Their Safety and Susceptibility to Lantibiotics and Durancin ED26E/7

Goat milk has become a popular item of human consumption due to its originality. Enterococci are ubiquitous bacteria, and they can also be found in traditional dairy products. This study focuses on the safety of enterococci from Slovak raw goat milk and on their susceptibility to lantibiotic bacteriocins and durancin ED26E/7, which has not previously been studied. Biofilm formation ability in enterococci, virulence factor genes, enzyme production and antibiotic profile were investigated. Samples of raw goat milk (53) were collected from 283 goats in Slovakia. MALDI-TOF mass spectrometry identified three enterococcal species: Enterococcus faecium, E. hirae and E. mundtii, with dominant occurrence of the species E. faecium. Low-grade biofilm formation ability (0.1 ≤ A570 < 1.0) was found in four strains of E. faecium. Gelatinase, hyaluronidase, aggregation substance and enterococcal surface protein genes were absent in these enterococci. Gene efaAfm (adhesin) was detected in five E. faecium strains. However, it was not detected in biofilm-forming strains. Enterococci detected in Slovak raw goat milk were found not to have pathogenic potential; four strains even produced high amounts of useful β-galactosidase. The strains were susceptible to lantibiotic bacteriocin treatment and to durancin ED26E/7 as well, which represents original information in dairy production.

Enterococci from pannon white rabbits: detection, identification, biofilm and screening for virulence factors

<p>Properties of enterococci isolated from the Hungarian breed Pannon White were studied to spread knowledge regarding the properties of microbiota in rabbits from the basic research standpoint and to select a beneficial candidate for application in husbandry. Faeces from 113 Pannon White rabbits (mostly maternal line and some paternal line) were collected. They were sampled from rabbits varying in age and sex (82 kits, 6 does, 6 bucks, 19 adult rabbits), which were aged 2 wk (14 suckling rabbits), 6 and 8 wk (68 weaning and post-weaning rabbits), adult rabbits (31, one year). Faecal mixtures were sampled into sterile packs with faeces from 5-6 animals in each. The total count of enterococci from these Pannon White rabbits reached, on av. 5.28±0.29 colony forming units/g (log10). Among the 19 enterococci, 14 <em>E. faecalis</em> and 5 <em>E. faecium</em> were detected using 3 identification methods. The enterococci were mostly resistant to antibiotics. They were non-haemolytic, Dnase and urease negative. They did not form biofilm. They were free of the <em>hylEfm</em> gene and <em>IS16</em> genes; the most frequently detected genes were <em>gelE</em>, <em>efaAfm</em>, <em>efaAfs</em>. Based on these results, <em>E. faecium</em> EF9a was selected for further analysis.</p>

Sensitivity to Enterocins of Biogenic Amine-Producing Faecal Enterococci from Ostriches and Pheasants

Enterococci are widespread bacteria forming the third largest genus among lactic acid bacteria. Some possess probiotic properties or they can produce beneficial proteinaceous antimicrobial substances called enterocins. On the other hand, some enterococci produce biogenic amines (BAs), so this study is focused on the sensitivity to enterocins of biogenic amine-producing faecal enterococci from ostriches and pheasants. Altogether, 60 enterococci isolated from faeces of ostriches and pheasants were tested for production of BAs. This target of the identified enterococci involved 46 strains selected from 140 ostriches and 17 from 60 pheasants involving the species Enterococcus hirae, E. faecium, E. faecalis, and E. mundtii. Although BAs histamine, cadaverine, putrescine, and tryptamine were not detected in the enterococci tested, in general high BA production by the tested enterococci was noted. The species E. hirae formed the majority of the enterococcal strains from ostrichs faeces (34 strains). High production of tyramine (TYM) was measured with an average amount of 958.16 ± 28.18 mg/ml. Among the enterococci from pheasants, the highest was production of TYM compared to phenylethylamine, spermidine, and spermine. Enterococci featured high BA production; however, they were sensitive to seven enterocins with inhibition activity ranging from 100 up to 25,600 AU/ml.