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Frontiers in Microbiology 2015Milk produced in udder cells is sterile but due to its high nutrient content, it can be a good growth substrate for contaminating bacteria. The quality of milk is... (Review)
Review
Milk produced in udder cells is sterile but due to its high nutrient content, it can be a good growth substrate for contaminating bacteria. The quality of milk is monitored via somatic cell counts and total bacterial counts, with prescribed regulatory limits to ensure quality and safety. Bacterial contaminants can cause disease, or spoilage of milk and its secondary products. Aerobic spore-forming bacteria, such as those from the genera Sporosarcina, Paenisporosarcina, Brevibacillus, Paenibacillus, Geobacillus and Bacillus, are a particular concern in this regard as they are able to survive industrial pasteurization and form biofilms within pipes and stainless steel equipment. These single or multiple-species biofilms become a reservoir of spoilage microorganisms and a cycle of contamination can be initiated. Indeed, previous studies have highlighted that these microorganisms are highly prevalent in dead ends, corners, cracks, crevices, gaskets, valves and the joints of stainless steel equipment used in the dairy manufacturing plants. Hence, adequate monitoring and control measures are essential to prevent spoilage and ensure consumer safety. Common controlling approaches include specific cleaning-in-place processes, chemical and biological biocides and other novel methods. In this review, we highlight the problems caused by these microorganisms, and discuss issues relating to their prevalence, monitoring thereof and control with respect to the dairy industry.
PubMed: 26733963
DOI: 10.3389/fmicb.2015.01418 -
Frontiers in Cellular and Infection... 2023Bladder cancer (BCa) is the most common malignancy of the urinary tract which can be divided into non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder...
BACKGROUND
Bladder cancer (BCa) is the most common malignancy of the urinary tract which can be divided into non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC), and their microbial differences are not fully understood. This study was conducted by performing 2bRAD sequencing for Microbiome (2bRAD-M) on NMIBC and MIBC tissue samples to investigate the microbiota differences between NMIBC and MIBC individuals.
METHODS
A total of 22 patients with BCa, including 7 NMIBC and 15 MIBC, were recruited. Tumor tissues were surgically removed as samples and DNA was extracted. Type IIB restriction endonucleases were used to enzymatically cleave the microbial genome for each microbe's tag and map it to species-specific 2bRAD markers to enable qualitative and quantitative studies of microbes between MIBC and NMIBC tissues.
RESULTS
A total of 527 species were detected. The microbial diversity of NMIBC tissues was significantly higher than that of MIBC tissues. Microbial composition of the two tumor tissues was similar, where Ralstonia_sp000620465 was the most dominant species. 4 species (Acinetobacter_guillouiae, Anoxybacillus_A_rupiensis, Brevibacillus_agri and Staphylococcus_lugdunensis) were enriched in NMIBC, while Ralstonia_mannitolilytica, Ralstonia_pickettii, and Ralstonia_sp000620465 were overrepresented in MIBC. 252 discriminatory character taxa were also revealed by linear discriminant analysis effect sizea (LEfSe). Species importance point plots identified Ralstonia_sp000620465, Cutibacterium_acnes and Ralstonia_pickettii as the three most important species between the two groups. Meanwhile, functional annotation analysis showed 3011 different COGs and 344 related signaling pathways between MIBC and NMIBC microbiome.
CONCLUSION
This first 2bRAD-M microbiome study on MIBC and NMIBC tissues revealed significant differences in the microbial environment between the two groups, which implies a potential association between tumor microbial dysbiosis and BCa, and provides a possible target and basis for subsequent studies on the mechanisms of BCa development and progression.
Topics: Humans; Urinary Bladder; Urinary Bladder Neoplasms; Neoplasm Invasiveness
PubMed: 37351184
DOI: 10.3389/fcimb.2023.1182322 -
Antibiotics (Basel, Switzerland) Jan 2022Modified antimicrobial and antifouling materials and surfaces can be used to limit the propagation of microorganisms on various surfaces and minimise the occurrence of...
Modified antimicrobial and antifouling materials and surfaces can be used to limit the propagation of microorganisms on various surfaces and minimise the occurrence of infection, transfer, and spoilage. Increased demand for 'green' solutions for material treatment has pushed the focus towards to naturally produced antimicrobials. Tyrocidines, cyclo-decapeptides naturally produced by a soil bacterium , have a broad spectrum of activity against Gram-positive and Gram-negative bacteria, filamentous fungi, and yeasts. Continual losses in tyrocidine production highlighted the possible association of peptides to surfaces. It was found in this study that tyrocidines readily associates with many materials, with a selectivity towards polysaccharide-type materials, such as cellulose. Peptide-treated cellulose was found to remain active after exposure to a broad pH range, various temperatures, salt solutions, water washes, and organic solvents, with the sterilising activity only affected by 1% SDS and 70% acetonitrile. Furthermore, a comparison to other antimicrobial peptides showed the association between tyrocidines and cellulose to be unique in terms of antimicrobial activity. The robust association between the tyrocidines and various materials holds great promise in applications focused on preventing surface contamination and creating self-sterilising materials.
PubMed: 35203778
DOI: 10.3390/antibiotics11020174 -
Insects Sep 2013Brevibacillus laterosporus, a bacterium characterized by the production of a unique canoe-shaped lamellar body attached to one side of the spore, is a natural inhabitant... (Review)
Review
Brevibacillus laterosporus, a bacterium characterized by the production of a unique canoe-shaped lamellar body attached to one side of the spore, is a natural inhabitant of water, soil and insects. Its biopesticidal potential has been reported against insects in different orders including Coleoptera, Lepidoptera, Diptera and against nematodes and mollusks. In addition to its pathogenicity against invertebrates, different B. laterosporus strains show a broad-spectrum antimicrobial activity including activity against phytopathogenic bacteria and fungi. A wide variety of molecules, including proteins and antibiotics, have been associated with the observed pathogenicity and mode of action. Before being considered as a biological control agent against plant pathogens, the antifungal and antibacterial properties of certain B. laterosporus strains have found medical interest, associated with the production of antibiotics with therapeutic effects. The recent whole genome sequencing of this species revealed its potential to produce polyketides, nonribosomal peptides, and toxins. Another field of growing interest is the use of this bacterium for bioremediation of contaminated sites by exploiting its biodegradation properties. The aim of the present review is to gather and discuss all recent findings on this emerging entomopathogen, giving a wider picture of its complex and broad-spectrum biocontrol activity.
PubMed: 26462431
DOI: 10.3390/insects4030476 -
Gut Microbes 2023Although changes in gut microbiome have been associated with the development of T2D and its complications, the role of the gut virome remains largely unknown. Here, we...
Although changes in gut microbiome have been associated with the development of T2D and its complications, the role of the gut virome remains largely unknown. Here, we characterized the gut virome alterations in T2D and its complications diabetic nephropathy (DN) by metagenomic sequencing of fecal viral-like particles. Compared with controls, T2D subjects, especially those with DN, had significantly lower viral richness and diversity. 81 viral species were identified to be significantly altered in T2D subjects, including a decrease in some phages (e.g. and ). DN subjects were depleted of 12 viral species, including , and , and enriched in 2 phages ( and ). Multiple viral functions, particularly those of phage lysing host bacteria, were markedly reduced in T2D and DN. Strong viral-bacterial interactions in healthy controls were disrupted in both T2D and DN. Moreover, the combined use of gut viral and bacterial markers achieved a powerful diagnostic performance for T2D and DN, with AUC of 99.03% and 98.19%, respectively. Our results suggest that T2D and its complication DN are characterized by a significant decrease in gut viral diversity, changes in specific virus species, loss of multiple viral functions, and disruption of viral-bacterial correlations. The combined gut viral and bacterial markers have diagnostic potential for T2D and DN.
Topics: Humans; Gastrointestinal Microbiome; Diabetic Nephropathies; Virome; Diabetes Mellitus, Type 2; Bacteriophages; Bacteria
PubMed: 37349979
DOI: 10.1080/19490976.2023.2226925 -
Metabolites Nov 2022Lake Mariout is Egypt's degraded coastal marine habitat that encompasses a variety of wastes. The biodiversity and hard environmental conditions allow the co-existence...
Lake Mariout is Egypt's degraded coastal marine habitat that encompasses a variety of wastes. The biodiversity and hard environmental conditions allow the co-existence of organisms with high resistance and rich metabolism, making them potential candidates for screening and isolating novel microbial strains. A bacterial isolate (BF202) cultured from the marine sediments of Alexandria's Mariout Lake (Egypt) was tested for its antimicrobial and anticancer potential. The phylogenetic analysis of the isolated strain's and revealed that BF202 belongs to (). Antibiosis of was confirmed against microbial pathogens including , , and . The highest antibacterial activity was detected on glucose peptone medium after 18 h of incubation at 35 °C, and at pH of 7.0 in the presence of mannose and ammonium carbonate as carbon and nitrogen sources, respectively. The cytotoxicity of the methanolic extract against breast cancer (MCF-7) and normal Vero cell lines, using the MTT test, revealed IC values of 7.93 and 23.79 µg/mL, respectively. To identify apoptotic and necrotic cells, a flow cytometric analysis using annexin V-FITC/PI dual-labeling was utilized and recorded a higher number of necrotic cells compared to apoptotic ones. Similarly, the cell cycle S-phase arrest was reported. The LC-MS-MS investigation of extract and the molecular networking database analysis demonstrated five strategic diketopiperazine compounds with antimicrobial and anticancer activities. Taken together, this research shows that the crude extract of might be an effective agent against drug-resistant bacteria and malignant disorders due to its richness in diketopiperazines.
PubMed: 36422242
DOI: 10.3390/metabo12111102 -
3 Biotech Sep 2022Thermal hot springs are present throughout the world and constitute a unique habitat for microbial diversity. The current investigation is conducted to study the... (Review)
Review
Thermal hot springs are present throughout the world and constitute a unique habitat for microbial diversity. The current investigation is conducted to study the bacterial diversity of thermophilic microorganisms in thermal hot springs of the Indian Himalayan Region (IHR). As of today, 110 geothermal hot springs have been explored for microbial diversity. In this study, we observed that the growth of thermophilic bacteria isolated from thermal hot springs of IHR ranges between 40 and 100 °C, and pH of 3.5-8 have been reported in the literature. The major bacterial species reported from the thermal hot springs of IHR are spp., spp., spp., spp., , , etc. Furthermore, bacterial isolates from thermal hot springs of IHR have been reported to produce various enzymes and metabolites such as amylase, -galactosidase, cellulase, nitrate reductase, acetoin, caffeine degradation enzymes, lipase, urease, and laccase. Metagenomic study and the entire genomic shotgun project have established the impact of physicochemical parameters (temperature and pH) on developing the microbiome. We have discussed the discoveries of microbiological data on the hot springs of IHR until the end of year 2021. As a whole, the microbiome adapts themselves as successful inhabitants to extreme environmental conditions and also serves as a diverse resource for potential applications in health, food, and environment.
PubMed: 36003895
DOI: 10.1007/s13205-022-03270-8 -
Microorganisms Jul 2021The microbial diversity of high-altitude geothermal springs has been recently assessed to explore their biotechnological potential. However, little is known regarding... (Review)
Review
The microbial diversity of high-altitude geothermal springs has been recently assessed to explore their biotechnological potential. However, little is known regarding the microbiota of similar ecosystems located on the Armenian Highland. This review summarizes the known information on the microbiota of nine high-altitude mineralized geothermal springs (temperature range 25.8-70 °C and pH range 6.0-7.5) in Armenia and Nagorno-Karabakh. All these geothermal springs are at altitudes ranging from 960-2090 m above sea level and are located on the Alpide (Alpine-Himalayan) orogenic belt, a seismically active region. A mixed-cation mixed-anion composition, with total mineralization of 0.5 mg/L, has been identified for these thermal springs. The taxonomic diversity of hot spring microbiomes has been examined using culture-independent approaches, including denaturing gradient gel electrophoresis (DGGE), 16S rRNA gene library construction, 454 pyrosequencing, and Illumina HiSeq. The bacterial phyla Proteobacteria, Bacteroidetes, Cyanobacteria, and Firmicutes are the predominant life forms in the studied springs. Archaea mainly include the phyla Euryarchaeota, Crenarchaeota, and Thaumarchaeota, and comprise less than 1% of the prokaryotic community. Comparison of microbial diversity in springs from Karvachar with that described for other terrestrial hot springs revealed that Proteobacteria, Bacteroidetes, Actinobacteria, and Deinococcus-Thermus are the common bacterial groups in terrestrial hot springs. Contemporaneously, specific bacterial and archaeal taxa were observed in different springs. Evaluation of the carbon, sulfur, and nitrogen metabolism in these hot spring communities has revealed diversity in terms of metabolic activity. Temperature seems to be an important factor in shaping the microbial communities of these springs. Overall, the diversity and richness of the microbiota are negatively affected by increasing temperature. Other abiotic factors, including pH, mineralization, and geological history, also impact the structure and function of the microbial community. More than 130 bacterial and archaeal strains (, , and ) have been reported, some of which may be representative of novel species (sharing 91-97% sequence identity with their closest matches in GenBank) and producers of thermozymes and biomolecules with potential biotechnological applications. Whole-genome shotgun sequencing of K1, as well as of the potentially new sp. J25 and sp. K1, were performed. Most of the phyla identified by 16S rRNA were also identified using metagenomic approaches. Detailed characterization of thermophilic isolates indicate the potential of the studied springs as a source of biotechnologically valuable microbes and biomolecules.
PubMed: 34361908
DOI: 10.3390/microorganisms9071473 -
PloS One 2019Bacteria active against multi-drug resistant pathogens, isolated by direct selection of colonies from clover silage samples, produce zones of inhibition against two...
Bacteria active against multi-drug resistant pathogens, isolated by direct selection of colonies from clover silage samples, produce zones of inhibition against two Gram-negative (Klebsiella pneumoniae Ni9 and Pseudomonas aeruginosa MMA83) and two Gram-positive (Staphylococcus aureus ATCC25923 and Listeria monocytogenes ATCC19111) pathogens. Isolates BGSP7, BGSP9, BGSP11 and BGSP12 produced the largest zones of inhibition against all four pathogens when grown in LB broth with aeration at 37°C. Isolates BGSP7, BGSP9, BGSP11 and BGSP12 were identified as Brevibacillus laterosporus and pulsed field gel electrophoresis and extracellular protein profiles showed that three different strains (BGSP7, BGSP9 and BGSP11) were isolated. A semi-native SDS-PAGE (sodium dodecyl sulphate-polyacrylamide gel electrophoresis) gel overlay assay showed that BGSP7 and BGSP9 produce small antimicrobial molecules of about 1.5 kDa, while BGSP11 produces antimicrobial molecules of 1.5 and 6 kDa active against S. aureus ATCC25923. Amino acid analysis of two antimicrobial molecules (1583.73 Da; from BGSP7 and 1556.31 Da; from BGSP11) revealed that they have a similar composition and differ only by virtue of the presence of a methionine which is present only in BGSP11 molecule. Genome sequencing of the three isolates revealed the presence of gene clusters associated with the production of non-ribosomally synthesized peptides (brevibacillin, bogorol, gramicidin S, plipastatin and tyrocin) and bacteriocins (laterosporulin, a lactococcin 972-like bacteriocin, as well as putative linocin M18, sactipeptide, UviB and lantipeptide-like molecules). Ultimately, the purification of a number of antimicrobial molecules from each isolate suggests that they can be considered as potent biocontrol strains that produce an arsenal of antimicrobial molecules active against Gram-positive and Gram-negative multi-resistant pathogens, fungi and insects.
Topics: Anti-Bacterial Agents; Bacteriocins; Brevibacillus; DNA, Bacterial; Gene Expression Regulation, Bacterial; Hot Temperature; Hydrogen-Ion Concentration; Kinetics; Microbial Sensitivity Tests; Silage
PubMed: 31075157
DOI: 10.1371/journal.pone.0216773 -
PloS One 2018This study aimed at isolating and identifying bacteria and fungi with the capacity to degrade low density polyethylene (LDPE). The level of biodegradation of LDPE sheets...
This study aimed at isolating and identifying bacteria and fungi with the capacity to degrade low density polyethylene (LDPE). The level of biodegradation of LDPE sheets with bacterial and fungal inoculums from different sampling points of Dandora dumpsite was evaluated under laboratory conditions. Incubation of the LDPE sheets was done for sixteen weeks at 37°C and 28°C for bacteria and fungi respectively in a shaker incubator. Isolation of effective candidates for biodegradation was done based on the recorded biodegradation outcomes. The extent of biodegradation on the polyethylene sheets was assessed by various techniques including weight loss analysis, Fourier Transform Infrared Spectroscopy (FTIR) and GC-MS. Fourier Transform Infra-Red spectroscopy (FTIR) analysis revealed the appearance of new functional groups attributed to hydrocarbon degradation after incubation with the bacteria and fungi. Analysis of the 16S rDNA and 18S rDNA sequences for bacteria and fungi respectively showed that bacteria belonging to genera Pseudomonas, Bacillus, Brevibacillus, Cellulosimicrobium, Lysinibacillus and fungi of genus Aspergillus were implicated as polyethylene degraders. An overall analysis confirmed that fungi are generally better degraders of polyethylene than bacteria. The highest fungal degradation activity was a mean weight reduction of 36.4±5.53% attributed to Aspergillus oryzae strain A5, 1 (MG779508). The highest degradation activity for bacteria was a mean of 35.72± 4.01% and 20.28± 2.30% attributed to Bacillus cereus strain A5,a (MG645264) and Brevibacillus borstelensis strain B2,2 (MG645267) respectively. Genus Aspergillus, Bacillus and Brevibacillus were confirmed to be good candidates for Low Density Poly Ethene bio-degradation. This was further confirmed by the appearance of the aldehyde, ether and carboxyl functional groups after FTIR analysis of the polythene sheets and the appearance of a ketone which is also an intermediary product in the culture media. To improve this degrading capacity through assessment of optimum conditions for microbial activity and enzyme production will enable these findings to be applied commercially and on a larger scale.
Topics: Bacteria; Biodegradable Plastics; Biodegradation, Environmental; Fungi; Humans; Kenya; Ketones; Polyethylene; RNA, Ribosomal, 16S; RNA, Ribosomal, 18S; Soil Microbiology; Spectroscopy, Fourier Transform Infrared
PubMed: 29979708
DOI: 10.1371/journal.pone.0198446