INTRODUCTION: The emergence and spread of antibiotic resistance among pathogenic bacteria drives the search for alternative antimicrobial therapies. Bacteriocins represent a potential alternative to antibiotic treatment. In contrast to antibiotics, bacteriocins are peptides or proteins that have relatively narrow spectra of antibacterial activities and are produced by a wide range of bacterial species. Bacteriocins of Escherichia coli are historically classified as microcins and colicins, and, until now, more than 30 different bacteriocin types have been identified and characterized. AREAS COVERED: We performed bibliographical searches of online databases to review the literature regarding bacteriocins produced by E. coli with respect to their occurrence, bacteriocin role in bacterial colonization and pathogenicity, and application of their antimicrobial effect. EXPERT OPINION: The potential use of bacteriocins for applications in human and animal medicine and the food industry includes (i) the use of bacteriocin-producing probiotic strains, (ii) recombinant production in plants and application in food, and (iii) application of purified bacteriocins.
- MeSH
- antibakteriální látky biosyntéza izolace a purifikace farmakologie MeSH
- bakteriociny biosyntéza izolace a purifikace farmakologie MeSH
- Escherichia coli metabolismus MeSH
- koliciny biosyntéza izolace a purifikace farmakologie MeSH
- lidé MeSH
- probiotika farmakologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
BACKGROUND: Optimal therapy for colorectal carcinoma (CRC), a frequently diagnosed malignancy, does not exist. Some of colicins and microcins, ribosomally synthesized peptides by gramnegative bacteria, have shown significant biological activity specifically against different cancer cells in vitro and in vivo conditions. The aim of this prospective study was to evaluate natural colicin and microcin production by large intestinal mucosal bacteria in each stage of colorectal neoplasia and in those with a history of colorectal neoplasia. METHODS: A total of 21 patients with non-advanced adenoma (non-a-A; 16/21 with current and 5/21 with history of non-a-A), 20 patients with advanced colorectal adenoma (a-A; 11/20 with current and 9/20 with history of a-A), 22 individuals with CRC (9/22 with current and 13/22 with history of CRC) and 20 controls were enrolled. Mucosal biopsies from the caecum, transverse colon and the rectum were taken during colonoscopy in each individual. Microbiological culture followed. Production of colicins and microcins was evaluated by PCR methods. RESULTS: A total of 239 mucosal biopsies were taken. Production of colicins and microcins was significantly more frequent in individuals with non-a-A, a-A and CRC compared to controls. No significant difference in colicin and microcin production was found between patients with current and previous non-a-A, a-A and CRC. Significantly more frequent production of colicins was observed in men compared to women at the stage of colorectal carcinoma. A later onset of increased production of microcins during the adenoma-carcinoma sequence has been observed in males compared to females. CONCLUSIONS: Strains isolated from large intestinal mucosa in patients with colorectal neoplasia produce colicins and microcins more frequently compared to controls. Bacteriocin production does not differ between patients with current and previous colorectal neoplasia. Fundamental differences in bacteriocin production have been confirmed between males and females.
The functional relevance of microbiota is a key aspect for understanding host-microbiota interactions. Mammalian skin harbours a complex consortium of beneficial microorganisms known to provide health and immune-boosting advantages. As yet, however, little is known about functional microbial communities on avian feathers, including their co-evolution with the host and factors determining feather microbiota (FM) diversity. Using 16S rRNA profiling, we investigated how host species identity, phylogeny and geographic origin determine FM in free-living passerine birds. Moreover, we estimated the relative abundance of bacteriocin-producing bacteria (BPB) and keratinolytic feather damaging bacteria (FDB) and evaluated the ability of BPB to affect FM diversity and relative abundance of FDB. Host species identity was associated with feather bacterial communities more strongly than host geographic origin. FM functional properties differed in terms of estimated BPB and FDB relative abundance, with both showing interspecific variation. FM diversity was negatively associated with BPB relative abundance across species, whereas BPB and FDB relative abundance was positively correlated. This study provides the first thorough evaluation of antimicrobial peptides-producing bacterial communities inhabiting the feather integument, including their likely potential to mediate niche-competition and to be associated with functional species-specific feather microbiota in avian hosts.
- MeSH
- Bacteria klasifikace genetika izolace a purifikace MeSH
- bakteriociny biosyntéza MeSH
- druhová specificita MeSH
- fylogeneze MeSH
- hostitelská specificita MeSH
- mikrobiota * MeSH
- peří mikrobiologie MeSH
- ptáci mikrobiologie MeSH
- RNA ribozomální 16S genetika MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An agar well diffusion assay (AWDA) was used to isolate a high bacteriocin-producing strain with a broad spectrum of antibacterial activity, strain MXG-68, from Inner Mongolia traditional fermented koumiss. Lactobacillus plantarum MXG-68 was identified by morphological, biochemical, and physiological characteristics and 16S rDNA analysis. The production of antibacterial substance followed a growth-interrelated model, starting at the late lag phase of 4 h and arriving at a maximum value in the middle of the stationary phase at 24 h. Antibacterial activity was abolished or decreased in the presence of pepsin, chymotrypsin, trypsin, proteinase, and papain K. The results showed that antibacterial substances produced by L. plantarum MXG-68 were proteinaceous and could thus be classified as the bacteriocin, named plantaricin MXG-68. The molar mass of plantaricin MXG-68 was estimated to be 6.5 kDa, and the amino acid sequence of its N-terminal was determined to be VYGPAGIFNT. The mode of plantaricin MXG-68 action was determined to be bactericidal. Bacteriocin in cell-free supernatant (CFS) at pH 7 was stable at different temperatures (60 °C, 80 °C, 100 °C, 121 °C for 30 min; 4 °C and - 20 °C for 30 days), as well as at pH 2.0-10.0. Antibacterial activity maintained stable after treatment with organic solvents, surfactants, and detergents but increased in response to EDTA. Response surface methodology (RSM) revealed the optimum conditions of bacteriocin production in L. plantarum MXG-68, and the bacteriocin production in medium optimized by RSM was 26.10% higher than that in the basal MRS medium.
- MeSH
- antibakteriální látky biosyntéza chemie farmakologie MeSH
- bakteriociny biosyntéza chemie farmakologie MeSH
- fylogeneze MeSH
- kinetika MeSH
- kultivační média MeSH
- kumys mikrobiologie MeSH
- Lactobacillus plantarum chemie klasifikace fyziologie MeSH
- molekulová hmotnost MeSH
- potravinářská mikrobiologie MeSH
- RNA ribozomální 16S genetika MeSH
- sekvence aminokyselin MeSH
- stabilita proteinů MeSH
- Staphylococcus účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Čína MeSH
- Klíčová slova
- postantibiotický průjem, průjem spojený s podáváním antibiotik, postantibiotická dysmikrobie,
- MeSH
- antibakteriální látky škodlivé účinky MeSH
- Bacillus MeSH
- bakteriální léková rezistence účinky léků MeSH
- bakteriociny biosyntéza MeSH
- fyziologie bakterií účinky léků MeSH
- lidé MeSH
- probiotika * farmakologie terapeutické užití MeSH
- průjem * farmakoterapie chemicky indukované prevence a kontrola MeSH
- pseudomembranózní enterokolitida * farmakoterapie chemicky indukované prevence a kontrola MeSH
- střevní mikroflóra účinky léků MeSH
- střevní sliznice mikrobiologie účinky léků MeSH
- Check Tag
- lidé MeSH
- Klíčová slova
- postantibiotický průjem, průjem spojený s podáváním antibiotik, postantibiotická dysmikrobie,
- MeSH
- antibakteriální látky škodlivé účinky MeSH
- Bacillus MeSH
- bakteriální léková rezistence účinky léků MeSH
- bakteriociny biosyntéza MeSH
- fyziologie bakterií účinky léků MeSH
- lidé MeSH
- probiotika * farmakologie terapeutické užití MeSH
- průjem * farmakoterapie chemicky indukované prevence a kontrola MeSH
- pseudomembranózní enterokolitida * farmakoterapie chemicky indukované prevence a kontrola MeSH
- střevní mikroflóra účinky léků MeSH
- střevní sliznice mikrobiologie účinky léků MeSH
- Check Tag
- lidé MeSH
Častým nežádoucím účinkem podávání širokospektrých antibiotik v dětském věku je střevní dysmikrobie, která se může projevovat např. průjmem. V prevenci tohoto stavu se osvědčilo podávání některých probioťttik. Pro účinnost probiotik v této indikaci je důležitá rezistence vůči antibiotikům. Z hlediska bezpečnosti je však také důležité, aby se tato rezistence nešířila z probiotika na patogenní mikroorganismy. Sporulující probiotikum Bacillus clausii, používané řadu let v různých indikacích včetně postantibiotických průjmů, se vyznačuje vysokou rezistencí vůči antibiotikům, která není přenosná na ostatní mikroorganismy, čímž splňuje standardní požadavky účinnosti a bezpečnosti terapie.
Lactobacillus species are usually used as starters for the production of fermented products, and some strains are capable of producing antimicrobial substances, such as bacteriocins. Because these characteristics are highly desirable, research are continually being performed for novel Lactobacillus strains with bacteriocinogenic potential for use by food industries. The aim of this study was to characterise the bacteriocinogenic potential and activity of Lactobacillus isolates. From a lactic acid bacteria culture collection obtained from raw milk and cheese, 27 isolates were identified by 16S rDNA as Lactobacillus spp. and selected for the detection of lantibiotics biosynthesis genes, bacteriocin production, antimicrobial spectra, and ideal incubation conditions for bacteriocin production. Based on the obtained results, 21 isolates presented at least one of the three lantibiotics biosynthesis genes (lanB, lanC or lamM), and 23 isolates also produced antimicrobial substances with sensitivity to at least one proteinase, indicating their bacteriocinogenic activity. In general, the isolates had broad inhibitory activity, mainly against Listeria spp. and Staphylococcus spp. strains, and the best antimicrobial performance of the isolates occurred when they were cultivated at 25 °C for 24 or 48 h or at 35 °C for 12 h. The present study identified the bacteriocinogenic potential of Lactobacillus isolates obtained from raw milk and cheese, suggesting their potential use as biopreservatives in foods.
- MeSH
- antibakteriální látky biosyntéza MeSH
- bakteriociny biosyntéza genetika MeSH
- biosyntetické dráhy genetika MeSH
- DNA bakterií chemie genetika MeSH
- Lactobacillus genetika izolace a purifikace metabolismus MeSH
- mikrobiální testy citlivosti MeSH
- mléko mikrobiologie MeSH
- ribozomální DNA chemie genetika MeSH
- RNA ribozomální 16S genetika MeSH
- sekvenční analýza DNA MeSH
- sýr mikrobiologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Medzi baktérie mliečneho kvasenia patrí niekoľko rodov gram pozitívnych baktérií, ktoré produkujú štruktúrne rôznorodé antimikróbne pôsobiace látky. V súčasnosti sú spomedzi nich v centre vedeckého záujmu práve bakteriocíny. Jedná sa o antimikróbne látky proteínovej povahy, ktoré sú produkované ribozomálne a majú zvyčajne úzke spektrum účinku na inhibíciu rastu baktérií. Podľa štruktúry a cieľa účinku ich rozdeľujeme do štyroch tried, ale existujú návrhy na vypracovanie nového spôsobu klasifikácie. Najzaujímavejšou a v praxi najvyužiteľnejšou triedou sú lantibiotiká, medzi ktoré patrí aj komerčne najpoužívanejší a najpreštudovanejší bakteriocín, nizín. Nepatogénny charakter baktérií mliečneho kvasenia je výhodný pre použitie nimi produkovaných bakteriocínov pri konzervovaní potravín, ako aj vo výživových doplnkoch alebo vo veterinárnej medicíne.
Lactic acid bacteria comprise several genera of gram–positive bacteria that are known for the production of structurally different antimicrobial substances. Among them, bacteriocins are nowadays in the centre of scientific interest. Bacteriocins, proteinaceous antimicrobial substances, are produced ribosomally and have usually a narrow spectrum of bacterial growth inhibition. According to their structure and the target of their activity, they are divided into four classes, although there are some suggestions for a renewed classification. The most interesting and usable class are lantibiotics. They comprise the most widely commercially used and well examined bacteriocin, nisin. The non-pathogenic character of lactic acid bacteria is advantageous for using their bacteriocins in food preservation as well as in feed supplements or in veterinary medicine.
BACKGROUND: Bacteriocin production is an important characteristic of E. coli strains of human origin. To date, 26 colicin and 9 microcin types have been analyzed on a molecular level allowing molecular detection of the corresponding genes. The production incidence of 29 bacteriocin types and E. coli phylogroups were tested in a set of 361 E. coli strains isolated from human urinary tract infections (UTI) and in 411 control strains isolated from feces of patients without bacterial gut infection. RESULTS: Production of 17 and 20 individual bacteriocin types was found in the UTI and control strains, respectively. Microcin H47 encoding determinants were found more often among UTI strains compared to controls (37.9% and 27.0% respectively, p = 0.02) and strains producing microcin H47 belonged predominantly to phylogroup B2 when compared to other bacteriocin producers (67.4% and 36.7%, respectively; p < 0.0001). Producers of 3 or more identified bacteriocin types were more common in the UTI group (20.0% compared to 12.4% in controls, p = 0.03). In the UTI strains, there was a markedly higher number of those producing colicin E1 compared to controls (22.1% to 10.2%, respectively, p = 0.0008). Moreover, colicin E1 production was more common in the UTI bacteriocinogenic strains with multi-producer capabilities. As shown by Southern blotting, pColE1 DNA was not recognized by the ColIa probe and vice versa suggesting that pColE1 was independently associated with pColIa in UTI strains. CONCLUSION: E. coli strains isolated from human urinary tract infections showed increased incidence of microcin H47 and colicin E1 production, respectively. Moreover, colicin E1 itself appears to be a potentially important virulence factor of certain uropathogenic E. coli strains.
- MeSH
- bakteriociny biosyntéza genetika MeSH
- Escherichia coli genetika izolace a purifikace metabolismus MeSH
- faktory virulence genetika metabolismus MeSH
- feces mikrobiologie MeSH
- infekce močového ústrojí mikrobiologie MeSH
- infekce vyvolané Escherichia coli mikrobiologie MeSH
- koliciny genetika metabolismus MeSH
- lidé MeSH
- uropatogenní Escherichia coli genetika izolace a purifikace metabolismus MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
