Racheal Oluwayemisi Fashogbon, Oyindamola John Samson, Theresa Abimbola Awotundun, Afolake Atinuke Olanbiwoninu, Bukola Christiana Adebayo-Tayo
{"title":"Microbial gamma-aminobutyric acid synthesis: a promising approach for functional food and pharmaceutical applications.","authors":"Racheal Oluwayemisi Fashogbon, Oyindamola John Samson, Theresa Abimbola Awotundun, Afolake Atinuke Olanbiwoninu, Bukola Christiana Adebayo-Tayo","doi":"10.1093/lambio/ovae122","DOIUrl":"10.1093/lambio/ovae122","url":null,"abstract":"<p><p>Gamma-aminobutyric acid (GABA) is a non-protein amino acid that is a main inhibitory neurotransmitter in the mammalian central nervous system. This mini-review emphasis on the microbial production of GABA and its potential benefits in various applications. Numerous microorganisms, including lactic acid bacteria, have been identified as efficient GABA producers. These microbes utilize glutamate decarboxylase enzymes to convert L-glutamate to GABA. Notable GABA-producing strains include Lactobacillus brevis, Lactobacillus plantarum, and certain Bifidobacterium species. Microbial GABA production offers numerous benefits over chemical synthesis, including cost-effectiveness, sustainability, and the potential for in situ production in fermented foods. Recent research has optimized fermentation conditions, genetic engineering approaches, and substrate utilization to enhance GABA yields. The benefits of GABA extend beyond its neurotransmitter role. Studies have shown its potential to reduce blood pressure, assuage anxiety, improve sleep quality, and improve cognitive function. These properties make microbial GABA production particularly attractive for developing functional foods, nutraceuticals, and pharmaceuticals. Future research directions include exploring novel GABA-producing strains, improving production efficiency, and investigating additional health benefits of microbially produced GABA.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142824293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characterization of the probiotic and functional properties of Enterococcus faecalis AQ10 isolated from chicken cecum.","authors":"Haichang Yin, Xinyu Zhang, Xinjie Jiang, Di Liu","doi":"10.1093/lambio/ovae116","DOIUrl":"10.1093/lambio/ovae116","url":null,"abstract":"<p><p>Lactic acid bacteria are considered the safest alternative to antibiotics and have a broad range of applications in animal husbandry. Enterococcus faecalis is a primary component of the chicken gut microbiota; it is known for its ability to regulate intestinal microbial balance and its probiotic functions. In this study, E. faecalis strain AQ10 from isolated from was the chicken cecum and used a combination of whole-genome sequencing and phenotypic analyses to investigate its probiotic properties. Whole-genome sequencing revealed that the genome length of E. faecalis AQ10 is 2.98 Mbp, with an average guanine-cytosine content of 38.12%, and includes 2832 protein-coding genes. Genome mining tools were used to identify an antimicrobial compound gene cluster. Additionally, E. faecalis AQ10 exhibited probiotic characteristics in vivo and antibacterial effects in vitro, with organic acids potentially contributing to its anti-Klebsiella pneumoniae activity. Metabolomics analyses revealed that the supernatant of E. faecalis AQ10 contained seven organic acids. In conclusion, E. faecalis AQ10 demonstrates significant probiotic potential and may be a suitable candidate for use in livestock and poultry breeding.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142895840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jung-Woo Shin, Yoon-Jung Shin, Dong-Yun Lee, Dong-Hyun Kim
{"title":"Alleviation of Helicobacter pylori- or aspirin-induced gastritis and neuroinflammation in mice by Lactococcus lactis and Bifidobacterium longum.","authors":"Jung-Woo Shin, Yoon-Jung Shin, Dong-Yun Lee, Dong-Hyun Kim","doi":"10.1093/lambio/ovae128","DOIUrl":"10.1093/lambio/ovae128","url":null,"abstract":"<p><p>Helicobacter pylori (HP) causes gastritis and peptic ulcer. Therefore, we examined whether probiotics Lactococcus lactis P135 and Bifidobacterium longum P142, which inhibited HP growth by 37.9% and 35.3%, respectively, and HP-induced IL-8 expression in KATO III cells by 68.6% and 63.1%, respectively, compared to those of normal controls, could mitigate HP-induced gastritis and psychiatric disorder in mice. Oral administration of P135 and/or P142 alleviated HP- or aspirin-induced gastritis, colitis, neuroinflammation, and depression/cognitive impairment-like behavior. They also suppressed HP infection, neutrophil infiltration, and NF-κB activation in the stomach and TNF-α expression and NF-κB activation in the colon and hippocampus. of P135 and/or P142 alleviated HP- or aspirin-induced gut dysbiosis: they decreased Lachnospiracease, Helicobacteriaceae, and Akkermansiaceae populations and increased Bacteroidaceae and Muribaculaceae populations. These findings suggest that HP growth/inflammation-inhibitory P135 and/or P142 may alleviate gut inflammation (gastritis and colitis) and neuroinflammation through the suppression of neutrophil infiltration, NF-κB activation, and HP growth, thereby leading to the attenuation of systemic inflammation and psychiatric disorder.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142818545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Modulating gut microbiota for treating antibiotic-associated diarrhea from Clostridium difficile infection: insights from Lizhong decoction and its polysaccharide component.","authors":"XinQian Rong, QingLong Shu","doi":"10.1093/lambio/ovae121","DOIUrl":"10.1093/lambio/ovae121","url":null,"abstract":"<p><p>To investigate whether the polysaccharide component of the Traditional Chinese Medicine (TCM) formula Lizhong decoction (LZD) has therapeutic effects and regulates gut microbiota in antibiotic-associated diarrhea (AAD) related to Clostridium difficile infection, a polysaccharide was extracted from LZD, consisting of rhamnose, five monosaccharides, arabinose, galactose, glucose, and galacturonic acid in a molar ratio of 1.12:8.49:4.06:80.67:5.66. An AAD model related to C. difficile infection was established using clindamycin gavage and oral colonization with C. difficile. Subsequently, oral treatment experiments with LZD polysaccharides and different doses of the decoction were conducted. The results indicated that the polysaccharide showed the best therapeutic effect on AAD related to C. difficile infection, with post-treatment gut microbiota clustering closest to the normal control group. The polysaccharide from LZD has therapeutic effects on AAD related to C. difficile infection, possibly achieved through the regulation of gut microbiota. It modulates the dominant gut microbiota, specifically increasing the abundance of beneficial bacteria by adjusting the ratio of Bacteroidetes and Firmicutes, thereby reversing the dysbiosis caused by C. difficile infection and antibiotics. Thus, LZD polysaccharide may be one of the important active components for gut microbiota regulation in this TCM formula.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142751234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Silu Zhang, Tian Liu, Xiaoli Zhou, Jun Wang, Tengxun Zhang, Guoxun Xiao, Song Huang, Chitong Rao, Xin Teng
{"title":"Isolation of Lactiplantibacillus plantarum for treatment of Salmonella infection in mice.","authors":"Silu Zhang, Tian Liu, Xiaoli Zhou, Jun Wang, Tengxun Zhang, Guoxun Xiao, Song Huang, Chitong Rao, Xin Teng","doi":"10.1093/lambio/ovae114","DOIUrl":"10.1093/lambio/ovae114","url":null,"abstract":"<p><p>Salmonella infections, often acquired through contaminated food or water, pose significant health risks, particularly amid rising antibiotic resistance and the adverse effects of conventional treatments on gut microbiota. This study isolated the probiotic Lactiplantibacillus plantarum GOLDGUT-LP618 from healthy human fecal samples, demonstrating its potential against Salmonella enterica. Lactiplantibacillus plantarum LP618 produced high levels of short-chain fatty acids (SCFAs) and exhibited robust inhibition of Salmonella in vitro. The strain showed resilience in gastric and bile environments, effectively curbing Salmonella growth. Post-infection treatment with L. plantarum LP618 significantly alleviated diarrhea, improved body weight, and moderated inflammatory responses. Histological analysis indicated restoration of intestinal structure, suggesting protection against mucosal damage. These results highlight L. plantarum LP618 as a promising probiotic candidate, offering a safe and effective alternative to antibiotics for managing Salmonella infections and promoting recovery in affected individuals.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Assessing the efficacy of postbiotics derived from Lactobacillus plantarum on antibiotic resistance genes in nosocomial pathogens such as Enterococcus faecalis and Pseudomonas aeruginosa.","authors":"Javad Nezhadi, Ali Ahmadi","doi":"10.1093/lambio/ovae127","DOIUrl":"10.1093/lambio/ovae127","url":null,"abstract":"<p><p>This study investigated the antibacterial and anti-biofilm properties of postbiotics derived from Lactobacillus plantarum and their effect on the expression of antibiotic resistance genes (ermB and blaKPC) in Enterococcus faecalis and Pseudomonas aeruginosa, respectively. Cell-free supernatants (CFSs) were analyzed through gas chromatography-mass spectrometry (GC-MS), which showed that butyric acid (14.31%) was the major compound, other metabolites present in CFSs included lactic acid (5.94%), hdroxyacetone (5,21%), benzoic acid (3.12%), Pyrrolo[1,2-a] pyrazine-1,4-dione (1.91%), 2,3-Butanediol (1.04%), and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (0.73.%). To investigate the effect of postbiotics on bacterial growth and biofilm formation, minimal inhibitory concentration (MIC) and microtiter plate assays were used. MIC results showed that resistant En. faecalis and P. aeruginosa can grow at concentrations of 2.5 and 5 mg/ml, respectively, after exposure to postbiotics. Furthermore, the microtiter plate results showed that postbiotics significantly reduced biofilm formation: 51%, 45%, and 39% in En. faecalis and 46%, 38%, and 27% in P. aeruginosa at different concentrations. Real-time polymerase chain reaction also confirmed the reduction of resistance genes (ermB; P = 0.007 and blaKPC; P = 0.02) expression. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed that the cell survival rate was 80%. These findings suggest that postbiotics from L. plantarum may be a promising approach for combating bacterial growth, biofilm formation, and antibiotic resistance.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142807120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yang Fu, Jing Luan, Lin Jiang, Xianzhen Li, Fan Yang, Zhimin Yu
{"title":"Paenibacillus oenotherae W2-3 degraded Welan gum to produce growth-promoting oligosaccharides.","authors":"Yang Fu, Jing Luan, Lin Jiang, Xianzhen Li, Fan Yang, Zhimin Yu","doi":"10.1093/lambio/ovae119","DOIUrl":"10.1093/lambio/ovae119","url":null,"abstract":"<p><p>Based on the biodegradation of Welan gum, this paper studies the properties of Welan gum degrading enzymes, degradation rules, and the application of Welan gum oligosaccharides. In order to study the biodegradation of Welan gum, a strain W2-3 capable of degrading Welan gum, was isolated from soil and identified as Paenibacillus sp. The properties of Welan gum degrading enzymes, degradation rules, and the application of Welan gum oligosaccharides were studied. After degradation, the average molecular weight of Welan gum oligosaccharides could be degraded to 500 Da, and the molecular weight distribution range was wide. Through the hydroponic culture of barley seedlings, it was proved that the degradation products of Welan gum had a positive effect on plant growth. The results showed that Welan gum oligosaccharides could significantly increase the root length, plant height, and fresh weight of barley, and could be used as a growth regulator in agricultural production.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142751288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Laura S E Haniford, Forest Dussault, Julie A Shay, Ashley Cooper, Burton W Blais, Calvin Ho-Fung Lau
{"title":"Bacterial composition and cultural dynamics of microgreens-associated microbiota during selective enrichment for Listeria monocytogenes.","authors":"Laura S E Haniford, Forest Dussault, Julie A Shay, Ashley Cooper, Burton W Blais, Calvin Ho-Fung Lau","doi":"10.1093/lambio/ovae113","DOIUrl":"10.1093/lambio/ovae113","url":null,"abstract":"<p><p>Widely regarded as a so-called \"superfood,\" microgreens have become an increasingly significant food crop from both nutritional and agricultural standpoints. However, similar to other produce commodities that are also cultivated using modernized indoor farming methods, there have been mounting concerns over the potential risks of consuming microgreens contaminated by Listeria monocytogenes. To gain insights into the microbial properties of microgreens, this study characterized the bacterial composition of fresh microgreen retail products using amplicon sequencing of 16S rRNA genes. Dominated by Gammaproteobacteria, a total of 36 shared genera were identified as putative constituents of the microgreen core microbiome. By monitoring the dynamics of microgreen-borne bacteria undergoing a Listeria-selective cultural enrichment procedure, it was revealed that, regardless of the presence or absence of L. monocytogenes, off-target bacteria of the Klebsiella and Enterococcus genera were significantly enriched from microgreens by the primary enrichment step, with the secondary enrichment step continuing to promote the expansion of Enterococcus population. While Listeria was generally neither the most-enriched nor the dominant taxon in cultures sampled at different enrichment stages, significant enrichment of Lysinibacillus and Bacillus bacteria was detected in microgreens contaminated with L. monocytogenes, suggesting they could be co-enriched in competition with Listeria.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Biochemical characterization of HcrF from Limosilactobacillus fermentum, a NADH-dependent 2-ene reductase with activity on hydroxycinnamic acids.","authors":"Gautam Gaur, Michael Gänzle","doi":"10.1093/lambio/ovae109","DOIUrl":"10.1093/lambio/ovae109","url":null,"abstract":"<p><p>In fermented plant foods, phenolic compounds are metabolized by 2-ene reductases, which reduce double bonds adjacent to an aromatic rings in phytochemicals, including hydroxycinnamic acids, isoflavones, and flavones. Only few 2-ene reductases of lactic acid bacteria were characterized, including the hydrocinnamic reductases HcrB and Par1, and the daidzein reductase of Lactococcus lactis. This study aimed to characterize HcrF, a homologue of HcrB, in Limosilactobacillus fermentum. HcrF was purified after cloning in Escherichia coli and purification by affinity chromatography. HcrF was optimally active at 30°C-40°C and pH 7.0 and required both flavin mononucleotide and nicotinamide adenine dinucleotide as co-factors. Ferulic, caffeic, p-coumaric, and sinapic acids but not trans-cinnamic acids were reduced to dihydro derivatives. The maximum reaction velocity Vmax of HcrF was highest for ferulic acid. On a phylogenetic tree of 2-ene reductases, HcrF clustered most closely with the hydroxycinnamic acid reductase HcrB of Lactiplantibacillus plantarum. The hydroxycinnamic acid reductase Par1 of Furfurilactobacillus milii and flavone or isoflavone reductases were only distantly related to HcrF. In summary, current knowledge does not allow to predict the substrate specificity of 2-ene reductases on the basis of the protein sequence; this study adds HcrF to the short list of enzymes with known substrate specificity.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integrated neural network and PSO hybrid approach for production of citrulline using immobilized permeabilized Pseudomonas furukawaii.","authors":"Anubhuti Kawatra, Rakhi Dhankhar, Bharti Datten, Shweta Dhankhar, Deepak Chhabra, Pooja Gulati","doi":"10.1093/lambio/ovae111","DOIUrl":"10.1093/lambio/ovae111","url":null,"abstract":"<p><p>In the present study, nutraceutical citrulline was produced using immobilization of permeabilized whole cells of Pseudomonas furukawaii, an efficient producer of ADI. Since arginine deiminase (ADI) is intracellularly localized, various additives such as SDS (Sodium dodecyl sulfate), Triton X-100, and EDTA (Ethylenediaminetetraacetic Acid) were used to permeabilize the cell to improve substrate accessibility and ADI activity. The maximum ADI activity was observed with 0.25 mg ml-1 biomass concentration treated with 0.5 mmol l-1 EDTA for 15 min using OFAT (One factor at a time) approach. Optimization of permeabilization conditions of P. furukawaii cells using novel neural networks and particle swarm optimization led to maximum ADI activity with 0.10 mmol l-1 EDTA and 0.30 mg ml-1 biomass. Further, the morphological characterization of immobilized cells was assessed by field emission scanning electron microscopy and FTIR (Fourier transform infrared spectroscopy). An optimal citrulline production of 1.19 mmol l-1 was achieved at 2.5% sodium alginate with 20 mmol l-1 arginine at 38°C, and 180 min of incubation. The immobilized cells retained 90.3% productivity after seven reuse cycles. Thus, the formulated immobilized whole-cell biocatalyst, with higher stability offers cost-effective methods of citrulline production.</p>","PeriodicalId":17962,"journal":{"name":"Letters in Applied Microbiology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142682115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}