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BMC Genomics Oct 2023Exploring Brevibacterium strains from various ecosystems may lead to the discovery of new antibiotic-producing strains. Brevibacterium sp. H-BE7, a strain isolated from...
Exploring Brevibacterium strains from various ecosystems may lead to the discovery of new antibiotic-producing strains. Brevibacterium sp. H-BE7, a strain isolated from marine sediments from Northern Patagonia, Chile, had its genome sequenced to study the biosynthetic potential to produce novel natural products within the Brevibacterium genus. The genome sequences of 98 Brevibacterium strains, including strain H-BE7, were selected for a genomic analysis. A phylogenomic cladogram was generated, which divided the Brevibacterium strains into four major clades. A total of 25 strains are potentially unique new species according to Average Nucleotide Identity (ANIb) values. These strains were isolated from various environments, emphasizing the importance of exploring diverse ecosystems to discover the full diversity of Brevibacterium. Pangenome analysis of Brevibacterium strains revealed that only 2.5% of gene clusters are included within the core genome, and most gene clusters occur either as singletons or as cloud genes present in less than ten strains. Brevibacterium strains from various phylogenomic clades exhibit diverse BGCs. Specific groups of BGCs show clade-specific distribution patterns, such as siderophore BGCs and carotenoid-related BGCs. A group of clade IV-A Brevibacterium strains possess a clade-specific Polyketide synthase (PKS) BGCs that connects with phenazine-related BGCs. Within the PKS BGC, five genes, including the biosynthetic PKS gene, participate in the mevalonate pathway and exhibit similarities with the phenazine A BGC. However, additional core biosynthetic phenazine genes were exclusively discovered in nine Brevibacterium strains, primarily isolated from cheese. Evaluating the antibacterial activity of strain H-BE7, it exhibited antimicrobial activity against Salmonella enterica and Listeria monocytogenes. Chemical dereplication identified bioactive compounds, such as 1-methoxyphenazine in the crude extracts of strain H-BE7, which could be responsible of the observed antibacterial activity. While strain H-BE7 lacks the core phenazine biosynthetic genes, it produces 1-methoxyphenazine, indicating the presence of an unknown biosynthetic pathway for this compound. This suggests the existence of alternative biosynthetic pathways or promiscuous enzymes within H-BE7's genome.
Topics: Brevibacterium; Ecosystem; Genomics; Phylogeny; Anti-Bacterial Agents; Multigene Family; Phenazines
PubMed: 37858045
DOI: 10.1186/s12864-023-09694-7 -
IDCases 2022species are to be opportunistic pathogens. Although rare, several case reports have mentioned infections ranging from cutaneous infections to bacteremia. Here, we...
species are to be opportunistic pathogens. Although rare, several case reports have mentioned infections ranging from cutaneous infections to bacteremia. Here, we present a case report describing a 64-year-old male pancreatic cancer patient diagnosed with bacteremia.
PubMed: 36061140
DOI: 10.1016/j.idcr.2022.e01609 -
Applied and Environmental Microbiology Apr 2021ε-Poly-l-lysine is a potent antimicrobial produced through fermentation of and used in many Asian countries as a food preservative. It is synthesized and excreted by a...
ε-Poly-l-lysine is a potent antimicrobial produced through fermentation of and used in many Asian countries as a food preservative. It is synthesized and excreted by a special nonribosomal peptide synthetase (NRPS)-like enzyme called Pls. In this study, we discovered a gene from cheese bacterium that showed high similarity to the Pls from in terms of domain architecture and gene context. By cloning it into with a Pls promoter, we confirmed that its product is indeed ε-poly-l-lysine. A comprehensive sequence analysis suggested that Pls genes are widely spread among coryneform actinobacteria isolated from cheese and human skin; 14 out of 15 isolates and 10 out of 12 isolates contain it in their genomes. This finding raises the possibility that ε-poly-l-lysine as a bioactive secondary metabolite might be produced and play a role in the cheese and skin ecosystems. Every year, microbial contamination causes billions of tons of food wasted and millions of cases of illness. ε-Poly-l-lysine has potent, wide-spectrum inhibitory activity and is heat stable and biodegradable. It has been approved for food preservation by an increasing number of countries. ε-Poly-l-lysine is produced from soil bacteria of the genus , also producers of various antibiotic drugs and toxins and not considered to be a naturally occurring food component. The frequent finding of in cheese and skin bacteria suggests that ε-poly-l-lysine may naturally exist in cheese and on our skin, and ε-poly-l-lysine producers are not limited to filamentous actinobacteria.
Topics: Bacterial Proteins; Cheese; Cloning, Molecular; Corynebacterium; Humans; Peptide Synthases; Polylysine; Skin; Streptomyces; Streptomyces coelicolor
PubMed: 33712427
DOI: 10.1128/AEM.01841-20 -
3 Biotech Jan 2020Microbial strains capable of degrading petroleum hydrocarbons were isolated from the Yellow River Delta and screened for bio-surfactant production. The...
Microbial strains capable of degrading petroleum hydrocarbons were isolated from the Yellow River Delta and screened for bio-surfactant production. The bio-surfactant-producing characteristics of the isolates were evaluated, and all the isolates which could produce bio-surfactant were identified by 16S rRNA gene sequencing. The results showed that the isolates belong to sp. (72%), sp. (0.16%), sp. (0.06%) and sp. (0.06%). The biodegradability of crude oil, gasoline, diesel oil and other hydrocarbons by microbial strains were studied, among which the biodegrading ability of strain P1 and strain P19 is higher than other strains. Both strains P1 and P19 can degrade -hexane and -hexadecane effectively and have wide substrate extensiveness. In addition, Ni promoted the biodegradability of toluene by both strain P1 and strain P19, while Pb inhibited the growth of strain P19 and decreased its ability to biodegrade toluene. The studies revealed that microbes including strain P1 and strain P19 can be utilized in bioremediation of co-contaminated water with petroleum and heavy metals including Ni and Pb.
PubMed: 31879582
DOI: 10.1007/s13205-019-2011-2 -
Poultry Science Mar 2023The microbiota has received plenty of attention in recent years due to its influence on host health and productivity. The striped eggs have reduced hatching performance...
The microbiota has received plenty of attention in recent years due to its influence on host health and productivity. The striped eggs have reduced hatching performance and resulted in economic loss. The reasons are still unknown. Microbiota is one of the potentially important factors contributing to striped egg formation. This study investigates the relationship between the microbiota and striped eggs. The litter samples, feed samples, and cloacal swab samples of female ducks that produce striped eggs and normal eggs were performed for microbial diversity and composition using 16S rRNA sequencing. The results showed that there was no significant difference between feed microbiota and cloacal swab microbiota by alpha diversity, whereas, the number of microorganisms in the litter samples of female ducks that produced striped eggs was less than those of female ducks with normal eggs. There were compositional differences in litter microbiota of female ducks between the striped egg and the normal eggs. Among them, the abundance of Staphylococcus, Corynebacterium, and Brevibacterium in the litter of female ducks that produced striped eggs was significantly higher than that produced normal eggs. And these differential bacteria maybe affect the health of female ducks and cause abnormalities in the formation process of duck eggs. Therefore, the reduction of harmful bacteria may protect the reproductive health of female ducks and decrease the proportion of striped eggs. It provides an important reference to explore why female ducks produce striped eggs.
Topics: Animals; Female; Ducks; RNA, Ribosomal, 16S; Chickens; Ovum; Microbiota; Bacteria; Eggs
PubMed: 36623335
DOI: 10.1016/j.psj.2022.102436 -
Foods (Basel, Switzerland) Oct 2022is a fermented food product from maize, commonly consumed in Southern Africa. This study investigated the effect of optimizing fermentation (time and temperature) and...
is a fermented food product from maize, commonly consumed in Southern Africa. This study investigated the effect of optimizing fermentation (time and temperature) and boiling time of white maize (WM) and yellow maize (YM) , with the use of the Box-Behnken-response surface methodology (RSM). Fermentation time and temperature as well as boiling time were optimized and pH, total titratable acidity (TTA) and total soluble solids (TSS) determined. Results obtained showed that the processing conditions significantly ( ≤ 0.05) influenced the physicochemical properties. pH values of the samples ranged between 3.48-5.28 and 3.50-4.20 for YM and WM samples, respectively. Reduction in pH values after fermentation coincided with an increase in TTA as well as changes in the TSS values. Using the numerical multi-response optimisation of three investigated responses the optimal fermentation conditions were observed to be 25 °C for 54 h and a boiling time of 19 min for white maize and 29 °C for 72 h and a boiling time of 13 min for yellow maize . Thereafter white and yellow maize were prepared with the optimized conditions using different inocula (sorghum malt flour, wheat flour, millet malt flour or maize malt flour) and the pH, TTA and TSS of the derived samples determined. Additionally, amplicon sequencing of the 16S rRNA gene was used to characterise the relative abundance of bacterial genera in optimized samples, malted grains as well as flour samples. Major bacterial genera observed in the samples included , , , , , , , , , , , , , , , and , with variations noted for YM and WM . As a result, the variations in physicochemical properties are due to differences in maize type and modification in processing conditions. This study also discovered the existence of variety of bacterial that can be isolated for controlled fermentation of .
PubMed: 37430920
DOI: 10.3390/foods11203171 -
Animal Microbiome Oct 2021A major focus of research on the gut microbiota of poultry has been to define signatures of a healthy gut and identify microbiota components that correlate with feed...
BACKGROUND
A major focus of research on the gut microbiota of poultry has been to define signatures of a healthy gut and identify microbiota components that correlate with feed conversion. However, there is a high variation in individual gut microbiota profiles and their association with performance. Population level samples such as dust and pooled excreta could be useful to investigate bacterial signatures associated with productivity at the flock-level. This study was designed to investigate the bacterial signatures of high and low-performing commercial meat chicken farms in dust and pooled excreta samples. Poultry house dust and fresh pooled excreta were collected at days 7, 14, 21, 28 and 35 of age from 8 farms of two Australian integrator companies and 389 samples assessed by 16S ribosomal RNA gene amplicon sequencing. The farms were ranked as low (n = 4) or high performers (n = 4) based on feed conversion rate corrected by body weight.
RESULTS
Permutational analysis of variance based on Bray-Curtis dissimilarities using abundance data for bacterial community structure results showed that company explained the highest variation in the bacterial community structure in excreta (R = 0.21, p = 0.001) while age explained the highest variation in the bacterial community structure in dust (R = 0.13, p = 0.001). Farm performance explained the least variation in the bacterial community structure in both dust (R = 0.03, p = 0.001) and excreta (R = 0.01, p = 0.001) samples. However, specific bacterial taxa were found to be associated with high and low performance in both dust and excreta. The bacteria taxa associated with high-performing farms in dust or excreta found in this study were Enterococcus and Candidatus Arthromitus whereas bacterial taxa associated with low-performing farms included Nocardia, Lapillococcus, Brachybacterium, Ruania, Dietzia, Brevibacterium, Jeotgalicoccus, Corynebacterium and Aerococcus.
CONCLUSIONS
Dust and excreta could be useful for investigating bacterial signatures associated with high and low performance in commercial poultry farms. Further studies on a larger number of farms are needed to determine if the bacterial signatures found in this study are reproducible.
PubMed: 34600571
DOI: 10.1186/s42523-021-00127-y -
Frontiers in Microbiology 2022Plant-associated microbes play important roles in plant health and disease. is often found in the plant rhizosphere, and its possible functions are not well known,...
Plant-associated microbes play important roles in plant health and disease. is often found in the plant rhizosphere, and its possible functions are not well known, especially in medical plants. isolated from ginseng soil was used to investigate its effects on plant disease. The promoting properties and interactions with rhizospheric microorganisms were investigated in a medium. Further, a pot experiment was conducted to explore its effects on ginseng root rot disease. Physicochemical properties, high-throughput sequencing, network co-occurrence, distance-based redundancy analysis (db-RDA), and correlation analysis were used to evaluate their effects on the root rot pathogen. The results showed that YW25 had a high indoleacetic acid production capacity, and the maximum yield was 141.37 mg/L at 4 days. The growth of YW25 was inhibited by some probiotics (, , , , etc.) and potential pathogens (, , etc.), but it did not show sensitivity to the soil-borne pathogen . Pot experiments showed that could significantly alleviate the diseases caused by , and increased the available nitrogen and phosphorus content in rhizosphere soil. In addition, it enhanced the activities of soil sucrase and acid phosphatase. High-throughput results showed that the inoculation of with changed the microbial community structure of ginseng, stimulated the plant to recruit more plant growth-promoting bacteria, and constructed a more stable microbial network of ginseng root. In this study, we found and proved the potential of as a biocontrol agent against , providing a new idea for controlling soil-borne diseases of ginseng by regulating rhizosphere microorganisms.
PubMed: 35633727
DOI: 10.3389/fmicb.2022.850917 -
Poultry Science Dec 2023Efforts to achieve sustainable phosphorus (P) inputs in broiler farming which meet the physiological demand of animals include nutritional intervention strategies that...
Efforts to achieve sustainable phosphorus (P) inputs in broiler farming which meet the physiological demand of animals include nutritional intervention strategies that have the potential to modulate and utilize endogenous and microbiota-associated capacities. A temporal P conditioning strategy in broiler nutrition is promising as it induces endocrinal and transcriptional responses to maintain mineral homeostasis. In this context, the current study aims to evaluate the composition of the jejunal microbiota as a functional entity located at the main absorption site involved in nutrient metabolism. Starting from a medium or high P supply in the first weeks of life of broilers, a depletion strategy was applied at growth intervals from d 17 to 24 and d 25 to 37 to investigate the consequences on the composition of the jejunal microbiota. The results on fecal mineral P, calcium (Ca), and phytate contents showed that the diets applied to the depleted and non-depleted cohorts were effective. Microbial diversity in jejunum was represented by alpha diversity indices which appeared unaffected between dietary groups. However, chickens assigned to the dietary P depletion groups showed significantly higher abundances of Facklamia, Lachnospiraceae, and Ruminococcaceae compared to non-depleted control groups. Based on current knowledge of microbial function, these microorganisms make only a minor contribution to the birds' adaptive mechanism in the jejunum following P depletion. Microbial taxa such as Brevibacterium, Brachybacterium, and genera of the Staphylococcaceae family proliferated in a P-enriched environment and might be considered biomarkers for excessive P supply in commercial broiler chickens.
Topics: Animals; Phosphorus; Jejunum; Chickens; Minerals; Diet; Microbiota; Animal Feed; Dietary Supplements; Animal Nutritional Physiological Phenomena
PubMed: 37797492
DOI: 10.1016/j.psj.2023.103096 -
Insects May 2022Grasshoppers (Insecta, Orthoptera, Acridoidea) are a large group of agricultural and animal husbandry pests. They have a large food intake with high utilization of...
Grasshoppers (Insecta, Orthoptera, Acridoidea) are a large group of agricultural and animal husbandry pests. They have a large food intake with high utilization of plants fibers. However, the composition of the grasshopper gut microbial community, especially the relationship between gut microbial community and cellulose digestibility, remains unclear. In this research, 16S rRNA gene sequences were used to determine the intestinal microbial diversity of , , and , and Spearman correlation analysis was performed between the intestinal microbes of grasshoppers and the digestibility of cellulose and hemicellulose. The results showed that Proteobacteria was the dominant phylum and was the dominant genus in the guts of the four species of grasshoppers; there was no significant difference in the species composition of the gut microbes of the four species of grasshoppers. Spearman correlation analysis showed that and were significantly correlated with cellulose digestibility. , , and were significantly associated with hemicellulose digestibility. Our results confirmed that the gut microbes of grasshoppers were correlated with the digestibility of cellulose and hemicellulose, and indicated that grasshoppers may have the potential to develop into bioreactors, which can be applied to improve straw utilization efficiency in the future.
PubMed: 35621768
DOI: 10.3390/insects13050432