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Four primers targeting the self-sufficient cytochrome P450 monooxygenase gene in the Bacillus cereus group were designed in this study. PCR was carried out using these primers, and Bacillus thuringiensis wild type strains C32 and 1.2 as well as the reference strain HER1410 were proven to possess this gene. Our results also showed that B. thuringiensis C32 possesses two different copies of this gene. Phylogenetic analysis and comparative sequence analysis were performed in order to evaluate the differences between the sequences of B. thuringiensis C32, 1.2 and HER1410 as well as those from the public databases. The sequence of B. thuringiensis HER1410 clustered with that of B. cereus 14579T, and the sequences of B. thuringiensis C32 and 1.2 clustered with that of Bacillus weihenstephanensis KBAB4. The sequences of both B. thuringiensis Al Hakam and B. thuringiensis serovar konkukian 97-27 did not cluster with strains C32, 1.2 and HER1410. The diversity of CYP102A in B. thuringiensis strains implies that this species represents an excellent potential resource of different self-sufficient cytochrome P450 monooxygenases. [ABSTRACT FROM AUTHOR]

We present an easy, fast and accurate method for the identification of Geobacillus stearothermophilus - the type species of the genus Geobacillus. We used 16S rRNA gene restriction analysis with AluI and demonstrated a discriminate restriction profile of this species. The presence of a fragment 162 bp in size and the absence of the 76 bp and 86 bp fragments was identified to be characterictic of the species G. stearothermophilus. For the further validation of the applicability of restriction analysis for the species identification, G. stearothermophilus DSM 13240 as well as environmental thermophilic endospore-forming isolates 3, 9, 17, 30, 31, 32A, 35C and 36A were examined. Restriction profiles of all the environmental isolates were identical to that of G. stearothermophilus DSM 22T. The restriction pattern of DSM 13240 differed from these profiles, suggesting that this strain does not belong to the species G. stearothermophilus. The potential of 16S rRNA gene restriction analysis using AluI for identification of the other species of geobacilli is limited. [ABSTRACT FROM AUTHOR]

A high temperature-adapted bacteriophage, vB_PtoS_NIIg3.2 (NIIg3.2), was isolated in Lithuania from compost heaps using Parageobacillus toebii strain NIIg-3 as a host for phage propagation. Furthermore, NIIg3.2 was active against four strains of Geobacillus thermodenitrificans, and it infected the host cells from 50 to 80 °C. Transmission electron microscopy analysis revealed siphovirus morphology characterized by an isometric head (~59 nm in diameter) and a noncontractile tail (~226 nm in length). The double-stranded DNA genome of NIIg3.2 (38,970 bp) contained 71 probable protein-encoding genes and no genes for tRNA. In total, 29 NIIg3.2 ORFs were given a putative functional annotation, including those coding for the proteins responsible for DNA packaging, virion structure/morphogenesis, phage–host interactions, lysis/lysogeny, replication/regulation, and nucleotide metabolism. Based on comparative phylogenetic and bioinformatic analysis, NIIg3.2 cannot be assigned to any genus currently recognized by ICTV and potentially represents a new one within siphoviruses. The results of this study not only extend our knowledge about poorly explored thermophilic bacteriophages but also provide new insights for further investigation and understanding the evolution of Bacilllus-group bacteria-infecting viruses. [ABSTRACT FROM AUTHOR]

We report a detailed characterization of five thermophilic bacteriophages (phages) that were isolated from compost heaps in Vilnius, Lithuania using Geobacillus thermodenitrificans strains as the hosts for phage propagation. The efficiency of plating experiments revealed that phages formed plaques from 45 to 80 °C. Furthermore, most of the phages formed plaques surrounded by halo zones, indicating the presence of phage-encoded bacterial exopolysaccharide (EPS)-degrading depolymerases. Transmission Electron Microscopy (TEM) analysis revealed that all phages were siphoviruses characterized by an isometric head (from ~63 nm to ~67 nm in diameter) and a non-contractile flexible tail (from ~137 nm to ~150 nm in length). The genome sequencing resulted in genomes ranging from 38,161 to 39,016 bp. Comparative genomic and phylogenetic analysis revealed that all the isolated phages had no close relatives to date, and potentially represent three new genera within siphoviruses. The results of this study not only improve our knowledge about poorly explored thermophilic bacteriophages but also give new insights for further investigation of thermophilic and/or thermostable enzymes of bacterial viruses. [ABSTRACT FROM AUTHOR]

There is a growing interest in supporting human health by using prebiotics, such as oligosaccharides, and beneficial bacteria, also called probiotics. Combining these two components we can develop synbiotics. In order to create successful combination of synbiotic it is very important to evaluate the influence of prebiotic oligosaccharides to probiotic bacteria and their behavior, such as growth and secretion of health related biomolecules, including bacteriocins. In this study seven type strains of probiotic bacteria (five Lactobacillus sp. and two Lactococcus sp.) and two Lactobacillus sp. strains, isolated from probiotic yoghurt, were cultivated with various commercially available and extracted oligosaccharides (OS). The aim of this study was to evaluate the influence of these OS on type and isolated bacterial strains growth and antibacterial activity. Obtained results suggest that combination of certain OS with probiotic strains may considerably improve their growth and/or antibacterial activity. We also determined the antibacterial activity spectrum of investigated strains with combination of OS against common food borne pathogens. Results of this work show that prebiotic OS can be useful for modulating probiotic bacteria growth, antibacterial activity and even specificity of this activity. [ABSTRACT FROM AUTHOR]

D‐Tagatose is a rare natural sugar, which is promising alternative for popular dietary sweeteners. To optimize and make D‐tagatose production more cost‐effective, a portable (bio)sensor would be beneficial for D‐tagatose quantification in bioreactor media during D‐tagatose (bio)synthesis. In this study, a pilot study of D‐tagatose quantification by a bioamperometric system is reported. A key feature of the system is usage of fructose dehydrogenase from Gluconobacter japonicus, widely known as a highly fructose‐specific enzyme, and 2‐arylamino‐1,4‐benzoquinone derivatives, as electron transfer mediators from the enzyme to carbon electrodes. The system has been validated as biosensor for D‐tagatose quantification in the fermentation medium. [ABSTRACT FROM AUTHOR]

Collagens and collagen-like proteins are found in a wide range of organisms. The common feature of these proteins is a triple helix fold, requiring a characteristic pattern of amino acid sequences, composed of Gly-X-Y tripeptide repeats. Collagen-like proteins from bacteria are heterogeneous in terms of length and amino acid composition of their collagenous sequences. However, different bacteria live in different environments, some at extreme temperatures and conditions. This study explores the occurrence of collagen-like sequences in the genomes of different extreme condition-adapted bacteria, and investigates features that could be linked to conditions where they thrive. Our results show that proteins containing collagen-like sequences are encoded by genomes of various extremophiles. Some of these proteins contain conservative domains, characteristic of cell or endospore surface proteins, while most other proteins are unknown. The characteristics of collagenous sequences may depend on both, the phylogenetic relationship and the living conditions of the bacteria. • Collagen-like sequences (CLSs) are encoded in genomes of bacteria living in different extreme environments. • CLSs encoded by thermophilic bacteria are shorter compared to the CLSs of bacteria living at lower temperatures. • Pro-rich collagen-like sequences are more often in thermophilic bacteria. [ABSTRACT FROM AUTHOR]

Ability of bacteriocins to inhibit pathogenic bacteria may depend on the environment inhabited by the producing strain. However, there are just few reports on bacteriocin-producing thermophilic bacteria from unconventional environments. Therefore, in this work we investigated differences in antibacterial activity spectra of microorganisms isolated from two different environments: the oil wells (first collection) and surface soil above the oil pools (second collection). All strains were Gram-positive, rod-shaped, thermophilic and endospore forming bacteria. Using spot-on-lawn method we have demonstrated that strains from the second collection possess higher and broader antibacterial activity spectra than first collection strains. Furthermore, all strains were active against at least 1 of 19 tested pathogenic bacteria. Analysis of antibacterial compounds has shown that all of them were stable in broad temperature and pH ranges, sensitive to proteolytic enzymes, proving their proteonaceus nature. They were all secreted during the exponential growth phase and active against closely related thermophilic bacteria, which suggest that these substances are most likely bacteriocins. Most of the bacteriocins had molecular masses under 20 kDa. Plasmid isolation and elimination experiments suggest that bacteriocins are most likely chromosome-encoded. Our results confirm the differences between antibacterial spectra of bacteriocins produced by bacterial strains isolated from different environmental niches. [ABSTRACT FROM AUTHOR]