Applied Microbiology and Biotechnology最新文献

{"title":"The commercial PRRSV attenuated vaccine can be a potentially effective live trivalent vaccine vector","authors":"Yang Li,&nbsp;Yumiao Wang,&nbsp;Xiuxiu Pei,&nbsp;Yongshuai Wu,&nbsp;Shao Chen,&nbsp;Han Weng,&nbsp;Yang Jing,&nbsp;Zhiqian Ma,&nbsp;Zhiwei Li,&nbsp;Zifang Zheng,&nbsp;Yingtong Feng,&nbsp;Lele Xu,&nbsp;Xuyang Guo,&nbsp;Xiao Liu,&nbsp;Jianwu Zhang,&nbsp;Haixue Zheng,&nbsp;Shuqi Xiao","doi":"10.1007/s00253-025-13502-5","DOIUrl":"10.1007/s00253-025-13502-5","url":null,"abstract":"<p>PRRSV is an immunosuppressive virus that is prone to secondary infection by other viral and microbial pathogens, exacerbating its harm to pigs. The development of multivalent vaccines that can prevent and control multiple pathogens is of great significance for the pig industry. In order to evaluate the potential of commercial PRRSV vaccines as the viral vectors for the trivalent vaccine, this study first embedded <i>mCherry</i> or <i>EGFP</i> genes for fluorescent proteins into the infectious clone of the HP-PRRSV MLV vaccine strain GD to construct a recombinant strain. Furthermore, we constructed a recombinant PRRSV strain, rPRRSV-mCherry-EGFP, that expresses both EGFP and mCherry proteins simultaneously and evaluated the stability and immunogenicity of the exogenous proteins. The results showed that MARC-145 cells infected with rPRRSV-mCherry-EGFP could simultaneously express both EGFP and mCherry exogenous proteins, and the number of EGFP and mCherry positive cells increased with virus infection, providing more fluorescent tool options for virus visualization and high-throughput screening of anti-PRRSV drugs. More importantly, the recombinant rPRRSV-mCherry-EGFP can be passaged in MARC-145 cells for at least 10 generations. It can induce piglets to produce antibodies against PRRSV, EGFP, and mCherry, indicating that the embedded two exogenous genes can also induce good immune responses. Our research suggests that using the infectious clone of a commercial HP-PRRSV-attenuated vaccine as a vector and embedding immune genes of two other pathogens to construct a recombinant strain may be an effective attempt to achieve cross-protection against three pathogens, providing an important research basis for the design of trivalent vaccines.</p><p>• <i>A recombinant PRRSV that expressed two foreign proteins was constructed.</i></p><p>• <i>The recombinant PRRSV could induce antibodies against PRRSV, EGFP, and mCherry.</i></p><p>• <i>PRRSV MLV strain had the potential to be used as a viral vector for triple vaccines.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13502-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143900733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of red clover isoflavones on ruminal microbial composition and fermentation in dairy cows","authors":"Ying Bu,&nbsp;Xiaoyin Zhang,&nbsp;Zhanbo Xiong,&nbsp;Kexin Li,&nbsp;Shiqi Zhang,&nbsp;Miao Lin,&nbsp;Guoqi Zhao,&nbsp;Nan Zheng,&nbsp;Jiaqi Wang,&nbsp;Shengguo Zhao","doi":"10.1007/s00253-025-13497-z","DOIUrl":"10.1007/s00253-025-13497-z","url":null,"abstract":"<p>Red clover isoflavones, particularly biochanin A and formononetin, are known for their benefits in enhancing feed efficiency and nitrogen utilization in ruminants. However, their specific effects on rumen fermentation and microbial diversity remain insufficiently explored. This study investigated the impacts of red clover isoflavones on rumen function and bacterial diversity in dairy cows, utilizing both in vivo and in vitro methodologies. In the in vivo study, 40 Holstein dairy cows were allocated to four groups, each receiving red clover isoflavones at doses of 0, 0.4, 0.8, and 1.6 g/kg. Rumen fluid was collected for analysis of fermentation parameters, enzyme activity, and microbial composition through shotgun metagenomic sequencing. Concurrently, an in vitro rumen fermentation trial was conducted to evaluate the effects of biochanin A and formononetin on urea hydrolysis. Results from the in vivo experiments showed that red clover isoflavones significantly decreased ammonia nitrogen (NH₃-N) concentrations and urease activity in the rumen (<i>P</i> &lt; 0.05). Species level metagenomic analysis indicated a reduced abundance of proteolytic and ureolytic bacteria, such as <i>Prevotella</i> sp<i>002317355</i> and <i>Treponema_D bryantii_C</i>, with a corresponding increase in cellulolytic bacteria, including <i>Ruminococcus_D</i> sp<i>900319075</i> and <i>Ruminococcus_C</i> sp<i>000433635</i> (<i>P</i> &lt; 0.05). The in vitro trial further demonstrated that biochanin A and formononetin significantly reduced urea decomposition rates (<i>P</i> &lt; 0.05), with biochanin A exerting a more pronounced effect. These findings align with the observed reduction in ureolytic and proteolytic bacteria, along with an increase in cellulolytic bacteria across both trials. In conclusion, biochanin A emerged as the primary active component of red clover isoflavones, modulating urea nitrogen hydrolysis and rumen fermentation. This study substantiates previous findings and highlights the potential of red clover isoflavones for enhancing rumen microbial fermentation, offering a promising strategy for future dairy industry applications.</p><p><i>• Red clover isoflavones inhibit urease activity to decrease the abundance of urealytic bacteria.</i></p><p><i>• Biochanin A reduces ammonia nitrogen and urease activity, promoting protein efficiency.</i></p><p><i>• Red clover isoflavones may improve dairy cow rumen health and nitrogen utilization.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13497-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143888722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioreduction of N-(3-oxobutyl)heterocycles with flexible ring by yeast whole-cell biocatalysts","authors":"Máté Gergő Honvári,&nbsp;Bence Attila Kucsinka,&nbsp;Levente András Mócza,&nbsp;Pál Csuka,&nbsp;Viktória Bódai,&nbsp;László Poppe,&nbsp;Gábor Hornyánszky","doi":"10.1007/s00253-025-13486-2","DOIUrl":"10.1007/s00253-025-13486-2","url":null,"abstract":"<p>This study explored the bioreduction of <i>N</i>-(3-oxobutyl)heterocycles with (partially) saturated heterocyclic moieties using whole-cell forms of wild-type yeast strains and commercially available baker’s yeast (<i>Saccharomyces cerevisiae</i>). Eleven wild-type yeast strains and baker’s yeast were screened for ketoreductase activity on a series of five flexible <i>N</i>-heterocycles with prochiral carbonyl group in the <i>N</i>-(3-oxobutyl) substituent. Among the yeast strains tested, <i>Candida parapsilosis</i> (WY12) proved to be the most efficient biocatalyst in the bioreductions, resulting in the corresponding enantiopure alcohols—being promising chiral fragments with high level of drug-likeness—with good to excellent conversions (83–99%) and high enantiomeric excess (ee &gt; 99%). Other strains, such as <i>Pichia carsonii</i> (WY1) and <i>Lodderomyces elongisporus</i> (WY2), also showed promising ketoreductase activities with certain substrates. After screening as lyophilized whole cells, <i>C. parapsilosis</i> cells were immobilized in the form of calcium, zinc, nickel, and copper alginate beads. The whole-cell immobilization enabled recycling, with considerable residual activity of the biocatalyst over multiple cycles. Additionally, the study explored the scalability of these bioreductions, with immobilized <i>C. parapsilosis</i> delivering promising results. The use of immobilized cells simplified the work-up process and resulted in chiral alcohols with similar or even higher conversions to those observed in the screening reactions. Molecular docking of the five flexible <i>N</i>-heterocycles with prochiral carbonyl group into the active site of the experimental structure of the carbonyl reductase of <i>C. parapsilosis</i> rationalized their biocatalytic behavior and confirmed the assigned (<i>S</i>)-configuration of forming enantiopure alcohols.</p><p>• <i>Ketoreductase activity of eleven wild-type yeast strains and baker’s yeast were examined</i>.</p><p>• <i>Candida parapsilosis was subjected to whole-cell immobilization and recycling</i>.</p><p>• <i>Enantiopure alcohols with flexible N-heterocyclic units were produced at preparative scale</i>.</p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13486-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The aldehyde dehydrogenase superfamilies: correlations and deviations in structure and function","authors":"Johann Heider,&nbsp;Dominik Hege","doi":"10.1007/s00253-025-13467-5","DOIUrl":"10.1007/s00253-025-13467-5","url":null,"abstract":"<p>Aldehyde dehydrogenases participate in many biochemical pathways, either by degrading organic substrates via organic acids or by producing reactive aldehyde intermediates in many biosynthetic pathways, and are becoming increasingly important for constructing synthetic metabolic pathways. Although they consist of simple and highly conserved basic structural motifs, they exhibit a surprising variability in the reactions catalyzed. We attempt here to give an overview of the known enzymes of two superfamilies comprising the known aldehyde dehydrogenases, focusing on their structural similarities and the residues involved in the catalytic reactions. The analysis reveals that the enzymes of the two superfamilies share many common traits and probably have a common evolutionary origin. While all enzymes catalyzing irreversible aldehyde oxidation to acids exhibit a universally conserved reaction mechanism with shared catalytic active-site residues, the enzymes capable of reducing activated acids to aldehydes deviate from this mechanism, displaying different active-site modifications required to allow these reactions which apparently evolved independently in different enzyme subfamilies.</p><p><i>• The two aldehyde dehydrogenase superfamilies share significant similarities.</i></p><p><i>• Catalytic amino acids of irreversibly acting AlDH are universally conserved.</i></p><p><i>• Reductive or reversible reactions are enabled by water exclusion via the loss of conserved residues.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13467-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143888748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of two GH10 enzymes with ability to hydrolyze pretreated Sorghum bicolor bagasse","authors":"Camila Bruno Baron,&nbsp;María Laura Mon,&nbsp;Rubén Marrero Díaz de Villegas,&nbsp;Andrea Cattaneo,&nbsp;Paola Di Donato,&nbsp;Annarita Poli,&nbsp;Maria Emilia Negri,&nbsp;Mariana Alegre,&nbsp;Marcelo A. Soria,&nbsp;María Cecilia Rojo,&nbsp;Mariana Combina,&nbsp;Ilaria Finore,&nbsp;Paola M. Talia","doi":"10.1007/s00253-025-13484-4","DOIUrl":"10.1007/s00253-025-13484-4","url":null,"abstract":"<p>In this study, we characterized two novel enzymes of the glycoside hydrolase family 10 (GH10), Xyl10 C and Xyl10E, identified in the termite gut microbiome. The activities of both enzymes were assayed using beechwood xylan, barley β-glucan, and pretreated <i>Sorghum bicolor</i> bagasse (SBB) as substrates. Both enzymes, assessed individually and in combination, showed activity on beechwood xylan and pretreated SBB, whereas Xyl10E also showed activity on barley β-glucan. The composition of pretreated SBB mainly consisted of xylose and arabinose content. Purified Xyl10 C showed optimum xylanase activity in the pH range 7.0–8.0 and at a temperature of 50–60 °C, while Xyl10E was active at a wider pH range (5.0–10.0) and at 50 °C. The residual activities of Xyl10 C and Xyl10E after 8 h of incubation at 40 °C were 85% and 70%, respectively. The enzymatic activity of Xyl10 C increased to 115% in the presence of 5 M NaCl, was only inhibited in the presence of 0.5% sodium dodecyl sulfate (SDS), and decreased with β-mercaptoethanol. The xylanase and glucanase activities of Xyl10E were inhibited only in the presence of MnSO₄, NaCl, and SDS. The main hydrolysis enzymatic product of Xyl10 C and Xyl10E on pretreated SBB was xylobiose. In addition, the xylo-oligosaccharides produced by xylanase Xyl10E on pretreated SBB demonstrated promising antioxidant activity. Thus, the hydrolysis products using Xyl10E on pretreated SBB indicate potential for antioxidant activity and other valuable industrial applications.</p><p>• <i>Two novel GH10 xylanases from the termite gut microbiome were characterized.</i></p><p>• <i>Xylo-oligosaccharides obtained from sorghum bagasse exhibited antioxidant potential.</i></p><p>• <i>Both enzymes and their hydrolysis product have potential to add value to agro-waste.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13484-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143883664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cellulolytic and hemicellulolytic capacity of Acetivibrio clariflavus","authors":"Katarína Šuchová,&nbsp;Vladimír Puchart","doi":"10.1007/s00253-025-13471-9","DOIUrl":"10.1007/s00253-025-13471-9","url":null,"abstract":"<p>Lignocellulosic biomass represents the largest available renewable source of carbon. It is a recalcitrant mixture of different polysaccharides and lignin. For its complete degradation, a large set of enzymes capable of cleaving its individual components is required. Several anaerobic bacteria produce high-molecular-weight multienzyme complexes called cellulosomes where the enzymes work in synergy for efficient degradation of the complex plant material. One of the anaerobic thermophilic cellulosome-forming bacteria is <i>Acetivibrio clariflavus</i>. <i>Acetivibrio clariflavus</i> was found to be one of the most abundant lignocellulose-solubilizing bacteria in various plant decaying environments. It produces sophisticated cellulosomal complex that is most similar to mesophilic <i>Acetivibrio cellulolyticus</i> cellulosome. In comparison with other anaerobic cellulosome-forming bacteria <i>A</i>. <i>cellulolyticus</i> and <i>Acetivibrio thermocellus</i>, <i>A. clariflavus</i> possesses lower number of cellulolytic enzymes. However, it is significantly better equipped for a degradation of hemicellulose, particularly xylan. Some strains, e.g., 4 - 2a, were also shown to utilize xylose. Efficient saccharification of plant biomass makes <i>A. clariflavus</i> a promising candidate for various biotechnological applications including biofuel production.</p><p><i>• Acetivibrio clariflavus is anaerobic thermophilic cellulosome–forming bacterium.</i></p><p><i>• Its cellulosomes target mostly cellulose and hemicellulose, in particular xylan.</i></p><p><i>• The strains share most of xylanolytic enzymes but differ in xylose utilization.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13471-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143883663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single amino acid exchanges affect the substrate preference of an acetaldehyde dehydrogenase","authors":"Dominik Hege,&nbsp;Yvonne Gemmecker,&nbsp;Iris Schall,&nbsp;Paula Oppong-Nti,&nbsp;Georg Schmitt,&nbsp;Johann Heider","doi":"10.1007/s00253-025-13468-4","DOIUrl":"10.1007/s00253-025-13468-4","url":null,"abstract":"<p>The NAD⁺-dependent aldehyde dehydrogenase AldB from <i>Aromatoleum aromaticum</i> was recombinantly produced in <i>Escherichia coli</i> and biochemically characterized. As suggested by its substrate spectrum, the most probably physiological function of AldB is the oxidation of short aliphatic aldehydes such as acetaldehyde, which occur as intermediates in the degradation of the corresponding alcohols. In addition, we generated some mutant variants in residue Tyr460, which is located at the neck region of the substrate channel and analyzed their effects on the catalytic parameters for different substrates. Single amino acid exchanges at this position revealed profound changes in substrate preference and substrate inhibition of the variants.</p><p>• <i>Small aliphatic aldehydes show the best catalytic efficiency with aldehyde dehydrogenase AldB</i></p><p>• <i>Amino acid exchanges at Y460 results in changed catalytic efficiencies and substrate inhibition</i></p><p>• <i>AldB is a member of a new clade of the aldehyde dehydrogenase superfamily</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13468-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143871384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A neutralizing nanobody-based liquid-phase blocking ELISA to assess the protective potency of Senecavirus A vaccine","authors":"Suyu Mu,&nbsp;Songjia Pan,&nbsp;Hu Dong,&nbsp;Jinen Wu,&nbsp;Yun Zhang,&nbsp;Shuanghui Yin,&nbsp;Jianing Wang,&nbsp;Tian Wei,&nbsp;Xiaobo Wen,&nbsp;Huichen Guo,&nbsp;Shiqi Sun","doi":"10.1007/s00253-025-13492-4","DOIUrl":"10.1007/s00253-025-13492-4","url":null,"abstract":"<p><i>Senecavirus</i> A (SVA) causes swine blister diseases in the crown of hooves, abortion syndrome, and increased mortality rates in piglets. Vaccination is the best defense against SVA infection. However, evaluations of the efficacy of SVA vaccines currently rely on challenging pigs with SVA, which is time-consuming, labor-intensive, and inconsistent with animal welfare mandates. To establish a replacement for the virus neutralization test (VNT) and SVA challenge tests, we developed a liquid-phase blocking enzyme-linked immunosorbent assay (nbLPB-ELISA) based on V1-VHH as the coating antibody (Ab) and biotinylated V1-VHH as the detection Ab. Under optimized conditions, the VNT and nbLPB-ELISA results were strongly correlated (Pearson <i>R</i>² = 0.84; <i>p</i> &lt; 0.00001). Analysis of the LBP-ELISA and vaccine protection rate revealed that neutralizing Ab titers greater than 256 provided 100% protection, while titers of 64 and 128 offered 57.1% and 70% protection, respectively. The nbLPB-ELISA is a rapid, simple, safe, and cost-effective method of detecting SVA as a replacement for the SVA VNT and vaccine-challenge assays.</p><p><i>• We evaluated a specific, high-affinity, and neutralizing nanobody-targeting SVA.</i></p><p><i>• The developed nbLPB-ELISA can replace viral neutralization tests.</i></p><p><i>• The nbLPB-ELISA is suitable to evaluate protective immunity.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13492-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143865503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Profiling electric signals of electrogenic probiotic bacteria using self-attention analysis","authors":"Qing Chi,&nbsp;Jie Tang,&nbsp;Changqing Ji,&nbsp;Shan Chen,&nbsp;Qinquan Chen,&nbsp;Meikai Zeng,&nbsp;JiXing Cao,&nbsp;Shenxia Sun,&nbsp;Deron R. Herr,&nbsp;Qing-Gao Zhang,&nbsp;Zumin Wang,&nbsp;Chun-Ming Huang","doi":"10.1007/s00253-025-13425-1","DOIUrl":"10.1007/s00253-025-13425-1","url":null,"abstract":"<p>We fabricated a self-assembled electric circuit to detect the electrical signals produced by two electrogenic probiotic bacteria [<i>Leuconostoc mesenteroides</i> (<i>L. mesenteroides</i>) and <i>Lactococcus lactis</i> (<i>L. lactis</i>)] on chicken egg chorioallantoic membranes as well as in the intestine lumen of mice. Inoculation of <i>L. mesenteroides</i> or <i>L. lactis</i> plus glucose onto a ferrozine assay triggered the reduction of ferric ions to ferrous ions and the formation of ferrozine complexes, indicating the bacterial electron production. In the presence of glucose, <i>L. lactis</i> yielded higher electricity, measured by voltage changes, than <i>L. mesenteroides </i>in vitro. The spectra of the electrical signals generated by these two probiotic bacteria were highly distinguishable. We evaluated the importance of these differences with the application of a self-attention mechanism, a deep learning-based module, revealing several unique signals in the electrical spectra of <i>L. mesenteroides</i> as well as <i>L. lactis</i> bacteria. The specific electrical spectrum for each probiotic bacterium provided a dynamic signature for evaluation of the efficacy of various therapies using probiotics, antibiotics, and fecal microbiota transplantation in the future.</p><p>• <i> The electrical signals produced by probiotic bacteria L. mesenteroides and L. lactis on chicken egg chorioallantoic membranes and in the mouse intestine lumen were detectable.</i></p><p>• <i> In the presence of glucose, L. lactis yielded higher electricity than L. mesenteroides in vitro. Furthermore, the electrical spectra generated by these two bacteria were different.</i></p><p>• <i> The importance of these differences with the application of a self-attention mechanism revealed several unique signals in the electrical spectra.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13425-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143861300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a highly efficient base editing system for Lactobacilli to improve probiotics and dissect essential functions","authors":"Hitoshi Mitsunobu,&nbsp;Yudai Kita,&nbsp;Yumiko Nambu-Nishida,&nbsp;Shoko Miyazaki,&nbsp;Kensuke Nakajima,&nbsp;Ken-ichiro Taoka,&nbsp;Akihiko Kondo,&nbsp;Keiji Nishida","doi":"10.1007/s00253-025-13489-z","DOIUrl":"10.1007/s00253-025-13489-z","url":null,"abstract":"<p><i>Lactobacilli</i> play essential roles in the food industry and have a significant potential as probiotics and therapeutic agents. Genomic and genetic information has increasingly accumulated and been linked to their various functions, to which transgenic approaches are being performed to verify crucial genes. In order to reasonably develop more useful strains, beneficial traits need to be introduced into any given strains and enhanced or combined based on such genotype characterization. However, for practical use as probiotics or foods, organisms with transgene are hardly acceptable. Here, we have introduced the base editing Target-AID system specifically for <i>Lactobacilli</i>, enabling precise installation of point mutations without donor DNA and at multiple genomic loci simultaneously. <i>Lactiplantibacillus plantarum</i> has been successfully engineered to reduce production of imidazole propionate, which has been reported to be associated with type 2 diabetes by impairing glucose tolerance and insulin signaling. Additionally, this system enabled transient knock-out of an essential gene, such as one involved in cell division, resulting in severe filamentous cell phenotype. This demonstrates Target-AID is a promising genetic tool for <i>Lactobacilli</i> and can accelerate both applied and fundamental research.</p><p><i>• Efficient and multiplexable cytosine base editing established in Lactobacilli.</i></p><p><i>• Edited Lactobacillus reducing imidazole propionate associated with the risk of type 2 diabetes.</i></p><p><i>• Transient knock-out and dissection of an essential gene function.</i></p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":"109 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00253-025-13489-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143856414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}