Determination of foodborne pathogens in minced beef by real-time PCR without culture enrichment.

Meat provides the necessary environment for the growth of foodborne pathogens due to its features such as being rich in protein and having sufficient water activity. Listeria monocytogenes, Salmonella enterica, and Escherichia coli O157:H7, which can be transmitted through many foods, including water, and cause serious diseases, are among the significant pathogens. In the current study. Detection of Listeria monocytogenes, Escherichia coli and Salmonella enterica in 100 minced beef samples collected from different butchers and markets situated in the central districts of Erzurum province was performed by Real-Time PCR without pre-enrichment and DNA isolation. Linear regression equations of Ct values of standard pathogenic bacteria were created. Ct values of minced beef samples obtained as a result of Real-Time PCR analysis were substituted in the equations, and the amounts of pathogenic bacteria in the samples were determined. Listeria monocytogenes, Escherichia coli, and Salmonella enterica were detected in 45, 30, and 29 of 100 minced beef samples, respectively. It is known that the Real-Time PCR method, which is used to detect pathogenic bacteria, is more specific, fast, and reliable than conventional methods. According to the results obtained, it has been clearly observed that with our new approach, pathogenic bacteria growing on foods can be detected sensitively with less cost, shorter amount of time, and minimized workload without pre-enrichment and DNA isolation.

Anoxybacillus: an overview of a versatile genus with recent biotechnological applications.

The Bacillaceae family members are considered to be a good source of microbial factories for biotechnological processes. In contrast to Bacillus and Geobacillus, Anoxybacillus, which would be thermophilic and spore-forming group of bacteria, is a relatively new genus firstly proposed in the year of 2000. The development of thermostable microbial enzymes, waste management and bioremediation processes would be a crucial parameter in the industrial sectors. There has been increasing interest in Anoxybacillus strains for biotechnological applications. Therefore, various Anoxybacillus strains isolated from different habitats have been explored and identified for biotechnological and industrial purposes such as enzyme production, bioremediation and biodegradation of toxic compounds. Certain strains have ability to produce exopolysaccharides possessing biological activities including antimicrobial, antioxidant and anticancer. This current review provides past and recent discoveries regarding Anoxybacillus strains and their potential biotechnological applications in enzyme industry, environmental processes and medicine.

Evaluation of wool protein hydrolysate as peptone for production of microbial enzymes.

Peptones are one of the most expensive components of microbial culture media. The present study was conducted to test the usability of low-cost sheep wool peptone (SWP) as an organic nitrogen source in the production of six industrially important enzymes (lipase, amylase, tannase, pectinase, cellulase and invertase). SWP was prepared by alkaline hydrolysis and acid neutralization. Bacillus licheniformis and Aspergillus niger were selected as test microorganisms for enzyme production. To evaluate the efficacy of SWP in enzyme production, it was compared with commercial tryptone peptone (TP) in the shaking flask cultures of the test microorganisms. The optimum concentration of both SWP and TP was determined to be 8 g/L for the production of B. licheniformis-derived enzymes, but 6 g/L for the production of A. niger-derived enzymes. It was determined that SWP was superior to TP in the production of four enzymes (lipase, amylase, tannase and pectinase) of both B. licheniformis and A. niger. This is the first study about the usage of sheep wool protein hydrolysate (SWP) as an organic nitrogen source or a peptone in fermentative production of microbial enzymes.

Genome-based classification of Calidifontibacillus erzurumensis gen. nov., sp. nov., isolated from a hot spring in Turkey, with reclassification of Bacillus azotoformans as Calidifontibacillus azotoformans comb. nov. and Bacillus oryziterrae as Calidifontibacillus oryziterrae comb. nov.

A novel Gram-stain-positive, rod-shaped, endospore-forming, motile, aerobic bacterium, designated as P2T, was isolated from a hot spring water sample collected from Ilica-Erzurum, Turkey. Phylogenetic analyses based on 16S rRNA gene sequence comparisons affiliated strain P2T with the genus Bacillus, and the strain showed the highest sequence identity to Bacillus azotoformans NBRC 15712T (96.7 %). However, the pairwise sequence comparisons of the 16S rRNA genes revealed that strain P2T shared only 94.7 % sequence identity with Bacillus subtilis subsp. subtilis NCIB 3610T, indicating that strain P2T might not be a member of the genus Bacillus. The digital DNA-DNA hybridization and average nucleotide identity values between strain P2T and B. azotoformans NBRC 15712T were 19.8 and 74.2 %, respectively. The cell-wall peptidoglycan of strain P2T contained meso-diaminopimelic acid. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an aminophospholipid, five unidentified phospholipids and two unidentified lipids while the predominant isoprenoid quinone was MK-7. The major fatty acids were iso-C15 : 0 and iso-C16 : 0. The draft genome of strain P2T was composed of 82 contigs and found to be 3.5 Mb with 36.1 mol% G+C content. The results of phylogenomic and phenotypic analyses revealed that strain P2T represents a novel genus in the family Bacillaceae, for which the name Calidifontibacillus erzurumensis gen. nov., sp. nov. is proposed. The type strain of Calidifontibacillus erzurumensis is P2T (=CECT 9886T=DSM 107530T=NCCB 100675T). Based on the results of the present study, it is also suggested that Bacillus azotoformans and Bacillus oryziterrae should be transferred to this novel genus as Calidifontibacillus azotoformans comb. nov. and Calidifontibacillus oryziterrae comb. nov., respectively.

Bacillus pasinlerensis sp. nov., a thermophilic bacterium isolated from a hot spring in Turkey.

A Gram-reaction-positive, endospore-forming bacterium, designated strain P1T, was isolated from water samples collected from Pasinler Hot Spring and characterized using a polyphasic approach to clarify its taxonomic position. Strain P1T was found to have chemotaxonomic and morphological characteristics consistent with its classification in the genus Bacillus. The strain shared the highest 16S rRNA gene sequence identity values with Bacillus thermolactis R-6488T (97.6 %) and Bacillus kokeshiiformis MO-04T (97.2 %) and formed a distinct clade with both type strains in the phylogenetic trees based on 16S rRNA gene sequences. Strain P1T could grow optimally at 55 °C and in the presence of 2 % NaCl. The organism was found to contain meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The predominant menaquinone was determined to be MK-7. The major cellular fatty acids were identified as iso-C15 : 0, iso-C17 : 0 and anteiso-C17 : 0. Based upon the consensus of phenotypic and phylogenetic analyses, strain P1T represents a novel species of the genus Bacillus, for which the name Bacillus pasinlerensis sp. nov. is proposed. The type strain is P1T (=DSM 107529T=CECT 9885T=NCCB 100674T).