Pub Date : 2024-11-16DOI: 10.1016/j.micres.2024.127969
Jiarong Wang , Xiaoquan Yu , Hao Yang , Hanzhong Feng , Yujuan Wang , Nannan Zhang , Haining Xia , Jie Li , Lei Xing , Junfeng Wang , Yongxing He
The flagellum is a complex molecular nanomachine crucial for cell motility. Its assembly requires coordinated expression of over 50 flagellar genes, regulated by the transcription activator FleQ. Phylogenomic analyses suggest that many non-flagellated bacterial species have evolved from flagellated ancestors by losing specific flagellar components, though the evolutionary mechanisms driving this process remain unclear. In this study, we examined the evolutionary dynamics of Pseudomonas syringae DC3000 under standard laboratory conditions using quantitative proteomics. We observed a notable reduction in flagellar gene expression following prolonged serial passages. Whole-genome sequencing revealed multiple adaptive mutations in fleQ, dksA, and glnE, all of which are associated with flagellar biosynthesis. Furthermore, our findings demonstrate that nonmotile ΔfleQ cells can hitchhike onto wild-type cells, potentially facilitated by increased production of the surfactant syringafactin. Our study suggests that the high metabolic costs associated with flagella biosynthesis, coupled with advantageous hitchhiking properties, contribute to the degenerative evolution of flagella.
{"title":"Adapted evolution towards flagellar loss in Pseudomonas syringae","authors":"Jiarong Wang , Xiaoquan Yu , Hao Yang , Hanzhong Feng , Yujuan Wang , Nannan Zhang , Haining Xia , Jie Li , Lei Xing , Junfeng Wang , Yongxing He","doi":"10.1016/j.micres.2024.127969","DOIUrl":"10.1016/j.micres.2024.127969","url":null,"abstract":"<div><div>The flagellum is a complex molecular nanomachine crucial for cell motility. Its assembly requires coordinated expression of over 50 flagellar genes, regulated by the transcription activator FleQ. Phylogenomic analyses suggest that many non-flagellated bacterial species have evolved from flagellated ancestors by losing specific flagellar components, though the evolutionary mechanisms driving this process remain unclear. In this study, we examined the evolutionary dynamics of <em>Pseudomonas syringae</em> DC3000 under standard laboratory conditions using quantitative proteomics. We observed a notable reduction in flagellar gene expression following prolonged serial passages. Whole-genome sequencing revealed multiple adaptive mutations in <em>fleQ</em>, <em>dksA</em>, and <em>glnE</em>, all of which are associated with flagellar biosynthesis. Furthermore, our findings demonstrate that nonmotile Δ<em>fleQ</em> cells can hitchhike onto wild-type cells, potentially facilitated by increased production of the surfactant syringafactin. Our study suggests that the high metabolic costs associated with flagella biosynthesis, coupled with advantageous hitchhiking properties, contribute to the degenerative evolution of flagella.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127969"},"PeriodicalIF":6.1,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142676312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-15DOI: 10.1016/j.micres.2024.127974
Liang Luo , Qing Li , Chen Xing , Chenglong Li , Yantong Pan , He Sun , Xuezhi Yu , Kai Wen , Jianzhong Shen , Zhanhui Wang
The consecutive growth of antimicrobial resistance and the spread of resistance genes worldwide, especially the emergence of superbugs, have made traditional antibiotic-based treatments inadequate to fight bacterial infections. Therefore, new therapeutic modalities for bacterial infections are urgently needed. Antibodies are considered to be an effective alternative to antibiotics. The emergence and advancement of technologies such as hybridoma, antibody purification, transgenic mice, phage display, and protein engineering have enabled the production of large quantities of humanized antibodies with high purity and affinity. Antibodies has achieved remarkable achievements in the field of medicine in the past decades. Antibody-based therapy is expected to be an effective way to treat drug-resistant bacterial infections in the post-antibiotic era due to its merits of high specificity, which leads to no selective pressure on non-target bacteria and could cooperate with antibiotics to enhance the antimicrobial effect. This review first introduces the mechanism of action of antibodies against bacterial infections, then summarizes the reported antimicrobial antibodies according to different targets, discusses the advantages and limitations of the antibody-based therapy for antimicrobial treatment, and finally, the perspectives of antimicrobial antibodies developing have been prospected, providing a reference for the development of new antimicrobial antibodies.
{"title":"Antibody-based therapy: An alternative for antimicrobial treatment in the post-antibiotic era","authors":"Liang Luo , Qing Li , Chen Xing , Chenglong Li , Yantong Pan , He Sun , Xuezhi Yu , Kai Wen , Jianzhong Shen , Zhanhui Wang","doi":"10.1016/j.micres.2024.127974","DOIUrl":"10.1016/j.micres.2024.127974","url":null,"abstract":"<div><div>The consecutive growth of antimicrobial resistance and the spread of resistance genes worldwide, especially the emergence of superbugs, have made traditional antibiotic-based treatments inadequate to fight bacterial infections. Therefore, new therapeutic modalities for bacterial infections are urgently needed. Antibodies are considered to be an effective alternative to antibiotics. The emergence and advancement of technologies such as hybridoma, antibody purification, transgenic mice, phage display, and protein engineering have enabled the production of large quantities of humanized antibodies with high purity and affinity. Antibodies has achieved remarkable achievements in the field of medicine in the past decades. Antibody-based therapy is expected to be an effective way to treat drug-resistant bacterial infections in the post-antibiotic era due to its merits of high specificity, which leads to no selective pressure on non-target bacteria and could cooperate with antibiotics to enhance the antimicrobial effect. This review first introduces the mechanism of action of antibodies against bacterial infections, then summarizes the reported antimicrobial antibodies according to different targets, discusses the advantages and limitations of the antibody-based therapy for antimicrobial treatment, and finally, the perspectives of antimicrobial antibodies developing have been prospected, providing a reference for the development of new antimicrobial antibodies.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127974"},"PeriodicalIF":6.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142693070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-14DOI: 10.1016/j.micres.2024.127972
Min-Jeong Kim , Su-Kyung Shin , Ji-Won Han , Ji Eun Kim , Min Jee Lee , Heekyong R. Bae , Eun-Young Kwon
The anti-obesity effects of Lactobacillus paragasseri (L. paragasseri) have been reported, but the exact mechanisms have not been elucidated. There are also no reports on the impact of L. paragasseri on the gut microbiota environment. Recently, the incidence of sarcopenia due to obesity has increased regardless of age, exacerbating metabolic disorders caused by obesity. Therefore, we investigate the beneficial effects of L. paragasseri SBT2055 (LG2055) on obesity along with obese sarcopenia and gut microbiome changes. C57BL/6 J mice were fed a high-fat diet (HFD) and LG2055 (1×108 or 1×1010 CFU/mice, low-dose LG2055 (LP) or high-dose LG2055 (HP), respectively was administered orally. LG2055 supplementation significantly reduced white adipose tissues compared to the HFD group and modified plasma lipid profiles to normal levels. The anti-obesity efficacy of LG2055 was due to increased lipid excretion into feces by reducing the mRNA levels of fatty acid binding protein 1 (Fabp1), fatty acid binding protein 2 (Fabp2), fatty acid transport protein 4 (Fatp4), cluster of differentiation 36 (Cd36), and apolipoprotein 48 (ApoB48) in the small intestine. The body fat reduction inhibits ectopic lipid accumulation in the muscles, leading to improvements in muscle mass, grip strength, hind leg thickness, muscle protein levels, and muscle fiber size in both LP and HP groups. LG2055 increased gut microbiota diversity and elevated the levels of Bacteroidota, resulting in a lower Firmicutes/Bacteroidota ratio compared to the HFD group. Changes in the Bacteroidota showed a negative correlation with body fat and plasma free fatty acid (FFA) while exhibiting a positive correlation with lean body mass, grip strength, and hind leg thickness. Our results demonstrated the anti-obesity effects of LG2055 through the white adipose tissue (WAT)-muscle-gut axis, suggesting its potential as an anti-obesity agent.
{"title":"Lactobacillus paragasseri SBT2055 attenuates obesity via the adipose tissue-muscle-gut axis in obese mice","authors":"Min-Jeong Kim , Su-Kyung Shin , Ji-Won Han , Ji Eun Kim , Min Jee Lee , Heekyong R. Bae , Eun-Young Kwon","doi":"10.1016/j.micres.2024.127972","DOIUrl":"10.1016/j.micres.2024.127972","url":null,"abstract":"<div><div>The anti-obesity effects of <em>Lactobacillus paragasseri</em> (<em>L. paragasseri</em>) have been reported, but the exact mechanisms have not been elucidated. There are also no reports on the impact of <em>L. paragasseri</em> on the gut microbiota environment. Recently, the incidence of sarcopenia due to obesity has increased regardless of age, exacerbating metabolic disorders caused by obesity. Therefore, we investigate the beneficial effects of <em>L. paragasseri</em> SBT2055 (<em>LG2055</em>) on obesity along with obese sarcopenia and gut microbiome changes. C57BL/6 J mice were fed a high-fat diet (HFD) and <em>LG2055</em> (1×10<sup>8</sup> or 1×10<sup>10</sup> CFU/mice, low-dose LG2055 (LP) or high-dose LG2055 (HP), respectively was administered orally. <em>LG2055</em> supplementation significantly reduced white adipose tissues compared to the HFD group and modified plasma lipid profiles to normal levels. The anti-obesity efficacy of <em>LG2055</em> was due to increased lipid excretion into feces by reducing the mRNA levels of fatty acid binding protein 1 (Fabp1), fatty acid binding protein 2 (Fabp2), fatty acid transport protein 4 (Fatp4), cluster of differentiation 36 (Cd36), and apolipoprotein 48 (ApoB48) in the small intestine. The body fat reduction inhibits ectopic lipid accumulation in the muscles, leading to improvements in muscle mass, grip strength, hind leg thickness, muscle protein levels, and muscle fiber size in both LP and HP groups. <em>LG2055</em> increased gut microbiota diversity and elevated the levels of <em>Bacteroidota</em>, resulting in a lower <em>Firmicutes/Bacteroidota</em> ratio compared to the HFD group. Changes in the <em>Bacteroidota</em> showed a negative correlation with body fat and plasma free fatty acid (FFA) while exhibiting a positive correlation with lean body mass, grip strength, and hind leg thickness. Our results demonstrated the anti-obesity effects of <em>LG2055</em> through the white adipose tissue (WAT)-muscle-gut axis, suggesting its potential as an anti-obesity agent.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127972"},"PeriodicalIF":6.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142681650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Volatile organic compounds (VOCs) produced by microorganisms may have a noteworthy role in the control of plant pathogens. Xanthomonas are a well-studied group of phytobacteria that cause diverse diseases in economically important crops worldwide. Key species that infect sugarcane are X. albilineans (Xab) and X. axonopodis pv. vasculorum (Xav). Here, we investigated VOC-producing bacteria with antagonistic effects against Xab and Xav. We demonstrated that VOCs produced by Pseudomonas sp. V5-S-D11 was able to abolish the growth of these pathogens. A set of 32 VOCs was identified in the volatilome of V5-S-D11, with 10 showing a concentration-dependent inhibitory effect on both phytobacteria. Among them, dimethyl disulfide (DMDS), a volatile sulfur compound, has the potential to be biotechnologically explored in agriculture since it can improve plant growth and induce systemic resistance against plant pathogens. Interestingly, transcriptomic analysis of Xab treated with DMDS revealed several up-regulated metabolic pathways such as a two-component system, flagellar assembly, chemotaxis, and a bacterial secretion system. Although the ethanol (ETOH) used as DMDS solvent did not inhibit Xab growth, it triggered a similar up-regulation of some genes, indicating that this phytopathogen can deal with ETOH better than DMDS. Overall, this study explores the wide role of VOCs in the interactions with bacteria. Moreover, our results indicate that VOCs from Pseudomonas sp. may represent a novel biotechnological strategy to counteract diseases caused by Xanthomonas species and can be further exploited for sustainable approaches in agriculture.
{"title":"Inhibition of Xanthomonas growth by bioactive volatiles from Pseudomonas sp. triggers remarkable changes in the phytopathogen transcriptome","authors":"Luciane Fender Coerini , Aline Tieppo Nogueira Mulato , Joaquim Martins-Junior , Gabriela Felix Persinoti , Juliana Velasco de Castro Oliveira","doi":"10.1016/j.micres.2024.127971","DOIUrl":"10.1016/j.micres.2024.127971","url":null,"abstract":"<div><div>Volatile organic compounds (VOCs) produced by microorganisms may have a noteworthy role in the control of plant pathogens. <em>Xanthomonas</em> are a well-studied group of phytobacteria that cause diverse diseases in economically important crops worldwide. Key species that infect sugarcane are <em>X. albilineans</em> (Xab) and <em>X. axonopodis</em> pv. <em>vasculorum</em> (Xav)<em>.</em> Here, we investigated VOC-producing bacteria with antagonistic effects against Xab and Xav. We demonstrated that VOCs produced by <em>Pseudomonas</em> sp. V5-S-D11 was able to abolish the growth of these pathogens. A set of 32 VOCs was identified in the volatilome of V5-S-D11, with 10 showing a concentration-dependent inhibitory effect on both phytobacteria<em>.</em> Among them, dimethyl disulfide (DMDS), a volatile sulfur compound, has the potential to be biotechnologically explored in agriculture since it can improve plant growth and induce systemic resistance against plant pathogens. Interestingly<em>,</em> transcriptomic analysis of Xab treated with DMDS revealed several up-regulated metabolic pathways such as a two-component system, flagellar assembly, chemotaxis, and a bacterial secretion system. Although the ethanol (ETOH) used as DMDS solvent did not inhibit Xab growth, it triggered a similar up-regulation of some genes, indicating that this phytopathogen can deal with ETOH better than DMDS. Overall, this study explores the wide role of VOCs in the interactions with bacteria. Moreover, our results indicate that VOCs from <em>Pseudomonas</em> sp. may represent a novel biotechnological strategy to counteract diseases caused by <em>Xanthomonas</em> species and can be further exploited for sustainable approaches in agriculture.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127971"},"PeriodicalIF":6.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142687165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects joints and multiple organs and systems, which is long-lasting and challenging to cure and significantly impacting patients' quality of life. Alterations in the composition of intestinal flora in both preclinical and confirmed RA patients indicate that intestinal bacteria play a vital role in RA immune function. However, the mechanism by which the intestinal flora is regulated to improve the condition of RA is not fully understood. This paper reviews the methods of regulating gut microbiota and its metabolites through prebiotics, probiotics, and pharmacological interventions, and discusses their effects on RA. Additionally, it explores the potential predictive role of cellular therapy mechanisms of intestinal flora in treating RA. These findings suggest that restoring the ecological balance of intestinal flora and regulating intestinal barrier function may enhance immune system function, thereby improving rheumatoid arthritis. This offers new insights into its treatment.
类风湿性关节炎（RA）是一种慢性自身免疫性疾病，主要影响关节及多个器官和系统，病程长，治愈难度大，严重影响患者的生活质量。临床前和确诊的 RA 患者肠道菌群组成的改变表明，肠道细菌在 RA 免疫功能中发挥着重要作用。然而，调节肠道菌群以改善 RA 病情的机制尚未完全明了。本文回顾了通过益生菌、益生菌和药物干预来调节肠道微生物群及其代谢产物的方法，并讨论了它们对 RA 的影响。此外，本文还探讨了肠道菌群的细胞治疗机制在治疗 RA 方面的潜在预测作用。这些研究结果表明，恢复肠道菌群的生态平衡和调节肠道屏障功能可增强免疫系统功能，从而改善类风湿关节炎。这为类风湿关节炎的治疗提供了新的思路。
{"title":"Role of gut microbiota in rheumatoid arthritis: Potential cellular mechanisms regulated by prebiotic, probiotic, and pharmacological interventions","authors":"Jiashang Li, Ruoying Fan, Zhe Zhang, Lihui Zhao, Yu Han, Yue Zhu, Jin-ao Duan, Shulan Su","doi":"10.1016/j.micres.2024.127973","DOIUrl":"10.1016/j.micres.2024.127973","url":null,"abstract":"<div><div>Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects joints and multiple organs and systems, which is long-lasting and challenging to cure and significantly impacting patients' quality of life. Alterations in the composition of intestinal flora in both preclinical and confirmed RA patients indicate that intestinal bacteria play a vital role in RA immune function. However, the mechanism by which the intestinal flora is regulated to improve the condition of RA is not fully understood. This paper reviews the methods of regulating gut microbiota and its metabolites through prebiotics, probiotics, and pharmacological interventions, and discusses their effects on RA. Additionally, it explores the potential predictive role of cellular therapy mechanisms of intestinal flora in treating RA. These findings suggest that restoring the ecological balance of intestinal flora and regulating intestinal barrier function may enhance immune system function, thereby improving rheumatoid arthritis. This offers new insights into its treatment.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127973"},"PeriodicalIF":6.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Drought is a significant abiotic stress that adversely affects the physiological and biochemical processes in crops, posing a considerable challenge to agricultural productivity. The present study explored the efficacy of plant-derived biostimulant (PDB) and plant growth-promoting rhizobacteria (PGPR) strains Pseudomonas putida (RA) and Paenibacillus lentimorbus CHM12) in the management of negative impacts of drought stress in Zea mays (maize). Adathoda vasica leaf extracts (ADLE) emerged as the most potent biostimulant of the seven evaluated medicinal plant extracts. The synergetic effect of ADLE and RA enhances plant vegetative growth (root length, shoot length, fresh weight and dry weight) as well as significantly modulates drought-induced oxidative stress, as indicated by higher chlorophyll content and increased sugar and phenolic levels and reduction of proline level. The expression of defence-related (ZmAPX, ZmSOD, and ZmCAT) and transcription factor (ZmNAC, ZmWRKY, and ZmMYB) genes further supported the beneficial effects of this synergism under drought conditions. Furthermore, metabolite profiling through GC-MS analysis showed significant alterations in metabolites such as glucose, galactose, mannose, hexopyranose, linolenic acid, hexadecenoic acid, and butanedioic acid when PDB and PGPR were applied together. Overall, the findings of the present study affirm that the combined application of plant-derived biostimulant ADLE and plant-beneficial rhizobacteria RA can effectively alleviate the adverse effects of drought on maize, providing an eco-friendly and sustainable solution for improving productivity under stress.
{"title":"Synergistic effect of Adathoda vasica plant-derived biostimulant and PGPR on Zea mays L. for drought stress management","authors":"Abhilasha Mishra, Srishti Kar, Nikita Bisht, Shashank Kumar Mishra, Puneet Singh Chauhan","doi":"10.1016/j.micres.2024.127968","DOIUrl":"10.1016/j.micres.2024.127968","url":null,"abstract":"<div><div>Drought is a significant abiotic stress that adversely affects the physiological and biochemical processes in crops, posing a considerable challenge to agricultural productivity. The present study explored the efficacy of plant-derived biostimulant (PDB) and plant growth-promoting rhizobacteria (PGPR) strains <em>Pseudomonas putida</em> (RA) and <em>Paenibacillus lentimorbus</em> CHM12) in the management of negative impacts of drought stress in <em>Zea mays</em> (maize). <em>Adathoda vasica</em> leaf extracts (ADLE) emerged as the most potent biostimulant of the seven evaluated medicinal plant extracts. The synergetic effect of ADLE and RA enhances plant vegetative growth (root length, shoot length, fresh weight and dry weight) as well as significantly modulates drought-induced oxidative stress, as indicated by higher chlorophyll content and increased sugar and phenolic levels and reduction of proline level. The expression of defence-related (<em>ZmAPX, ZmSOD, and ZmCAT</em>) and transcription factor (<em>ZmNAC, ZmWRKY, and ZmMYB</em>) genes further supported the beneficial effects of this synergism under drought conditions. Furthermore, metabolite profiling through GC-MS analysis showed significant alterations in metabolites such as glucose, galactose, mannose, hexopyranose, linolenic acid, hexadecenoic acid, and butanedioic acid when PDB and PGPR were applied together. Overall, the findings of the present study affirm that the combined application of plant-derived biostimulant ADLE and plant-beneficial rhizobacteria RA can effectively alleviate the adverse effects of drought on maize, providing an eco-friendly and sustainable solution for improving productivity under stress.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127968"},"PeriodicalIF":6.1,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.micres.2024.127970
Gui-Ming Lin , Ju-Yuan Zhang , Zhi-Hui Shao , Chen Yang , Guo-Ping Zhao , Kai-Yao Huang , Cheng-Cai Zhang
PacR (All3953) has previously been identified as a global transcriptional regulator of carbon assimilation in cyanobacteria. In the facultative diazotrophic and filamentous cyanobacterium Anabaena PCC 7120 (Anabaena), inactivation of pacR has been shown to affect cell growth under various conditions. Nitrogen fixation in Anabaena occurs in heterocysts, cells differentiated semiregularly along the filaments following deprivation of combined nitrogen such as nitrate or ammonium. Here, we created a markerless deletion mutant of pacR. In addition to its growth defects observed under different light and nitrogen conditions, the mutant could form a high frequency of heterocysts, including heterocyst doublets, even in the presence of nitrate. Inactivation of pacR led to the upregulation of ntcA, a global regulator of nitrogen metabolism and heterocyst formation, as well as downregulation of genes involved in nitrate uptake and assimilation. These changes led to N-limited cells in the presence of nitrate. PacR also regulates most of the genes encoding bicarbonate transport systems. The promoter regions of ntcA, and several other genes involved in nitrogen or carbon uptake and assimilation, as well as patS and hetN involved in heterocyst patterning can be directly recognized by PacR in vitro. These findings, along with previously reported ChIP-seq data, establish PacR as a crucial transcriptional regulator for balancing carbon and nitrogen metabolism in cyanobacteria.
{"title":"The LysR-type transcriptional factor PacR controls heterocyst differentiation and C/N metabolism in the cyanobacterium Anabaena PCC 7120","authors":"Gui-Ming Lin , Ju-Yuan Zhang , Zhi-Hui Shao , Chen Yang , Guo-Ping Zhao , Kai-Yao Huang , Cheng-Cai Zhang","doi":"10.1016/j.micres.2024.127970","DOIUrl":"10.1016/j.micres.2024.127970","url":null,"abstract":"<div><div>PacR (All3953) has previously been identified as a global transcriptional regulator of carbon assimilation in cyanobacteria. In the facultative diazotrophic and filamentous cyanobacterium <em>Anabaena</em> PCC 7120 (<em>Anabaena</em>), inactivation of <em>pacR</em> has been shown to affect cell growth under various conditions. Nitrogen fixation in <em>Anabaena</em> occurs in heterocysts, cells differentiated semiregularly along the filaments following deprivation of combined nitrogen such as nitrate or ammonium. Here, we created a markerless deletion mutant of <em>pacR</em>. In addition to its growth defects observed under different light and nitrogen conditions, the mutant could form a high frequency of heterocysts, including heterocyst doublets, even in the presence of nitrate. Inactivation of <em>pacR</em> led to the upregulation of <em>ntcA</em>, a global regulator of nitrogen metabolism and heterocyst formation, as well as downregulation of genes involved in nitrate uptake and assimilation. These changes led to N-limited cells in the presence of nitrate. PacR also regulates most of the genes encoding bicarbonate transport systems. The promoter regions of <em>ntcA</em>, and several other genes involved in nitrogen or carbon uptake and assimilation, as well as <em>patS</em> and <em>hetN</em> involved in heterocyst patterning can be directly recognized by PacR <em>in vitro</em>. These findings, along with previously reported ChIP-seq data, establish PacR as a crucial transcriptional regulator for balancing carbon and nitrogen metabolism in cyanobacteria.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127970"},"PeriodicalIF":6.1,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142676314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-09DOI: 10.1016/j.micres.2024.127944
Maria Sequeira Lopes , Maria Daniela Silva , Joana Azeredo , Luís D.R. Melo
Coagulase-negative staphylococci (CoNS) are commensal bacteria of the human skin and mucosal membranes. The incidence of nosocomial infections caused by these species is on the rise, leading to a potential increase in antibiotic tolerance and resistance. Phages are emerging as a promising alternative to combat CoNS infections. Scientists are isolating phages infecting CoNS with a particular interest in S. epidermidis. This review compiles and analyses CoNS phages for several parameters including source, geographical location, host species, morphological diversity, and genomic diversity. Additionally, recent studies have highlighted the potential of these phages based on host range, in vitro evaluation of performance and stability, and interaction with biofilms. This comprehensive analysis enables a better understanding of the steps involved in using these phages for therapeutic purposes.
{"title":"Coagulase-Negative Staphylococci phages panorama: Genomic diversity and in vitro studies for a therapeutic use","authors":"Maria Sequeira Lopes , Maria Daniela Silva , Joana Azeredo , Luís D.R. Melo","doi":"10.1016/j.micres.2024.127944","DOIUrl":"10.1016/j.micres.2024.127944","url":null,"abstract":"<div><div>Coagulase-negative staphylococci (CoNS) are commensal bacteria of the human skin and mucosal membranes. The incidence of nosocomial infections caused by these species is on the rise, leading to a potential increase in antibiotic tolerance and resistance. Phages are emerging as a promising alternative to combat CoNS infections. Scientists are isolating phages infecting CoNS with a particular interest in <em>S. epidermidis</em>. This review compiles and analyses CoNS phages for several parameters including source, geographical location, host species, morphological diversity, and genomic diversity. Additionally, recent studies have highlighted the potential of these phages based on host range, <em>in vitro</em> evaluation of performance and stability, and interaction with biofilms. This comprehensive analysis enables a better understanding of the steps involved in using these phages for therapeutic purposes.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127944"},"PeriodicalIF":6.1,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142648688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-08DOI: 10.1016/j.micres.2024.127940
Ali kamran , Muhammad Dilshad Hussain , Tahir Farooq , Fangfang Li , Mehran Khan , Xiangyang Li , Sanwei Yang , Xin Xie
In a molecular-arm-race between viruses and their hosts, viruses have evolved to harness their host's post-translational modifications (PTMs) machinery to gain a competitive edge. These modifications are the most reliable target of plant viruses to overcome the host defence for successful infection. Relatively fewer PTMs i.e., phosphorylation, O-GlcNAcylation, Ubiquitination, and SUMOylation have been studied regulating the potyvirus-plant interaction. Therefore, it is worth drawing attention towards the importance and potential of this undermined but key strategy of potyvirids (members of family Potyviridae) to abduct their host defence line, suggesting to review in detail the existing knowledge of these PTMs and highlight the unexplored modifications that might have played their part in establishing successful infection. The current review provides an understanding of how PTMs execute viral replication and infection dynamics during plant-potyvirid interactions. We highlighted that PTMs linked to CP, NIa-pro, NIb, and VPg are important to specify their host, virulence, overcoming host innate immunity, and most importantly disarming the host of RNA silencing tool of nailing any intruder. The limitations and potential improvements in studying undermined PTMs, including acetylation, glycosylation, methylation, and neddylation, as well as challenges and future perspectives of this inevitable process are mechanistically deciphered in the course of plant-virus interactions. This communication opens new avenues for investigating the fundamental mechanisms of virus infection and the development of new antiviral strategies for sustainable disease managements.
{"title":"Deciphering intricate plant-virus interactions: Potyvirids orchestrate protein posttranslational modifications to regulate pathogenicity","authors":"Ali kamran , Muhammad Dilshad Hussain , Tahir Farooq , Fangfang Li , Mehran Khan , Xiangyang Li , Sanwei Yang , Xin Xie","doi":"10.1016/j.micres.2024.127940","DOIUrl":"10.1016/j.micres.2024.127940","url":null,"abstract":"<div><div>In a molecular-arm-race between viruses and their hosts, viruses have evolved to harness their host's post-translational modifications (PTMs) machinery to gain a competitive edge. These modifications are the most reliable target of plant viruses to overcome the host defence for successful infection. Relatively fewer PTMs i.e., phosphorylation, <em>O</em>-GlcNAcylation, Ubiquitination, and SUMOylation have been studied regulating the potyvirus-plant interaction. Therefore, it is worth drawing attention towards the importance and potential of this undermined but key strategy of potyvirids (members of family Potyviridae) to abduct their host defence line, suggesting to review in detail the existing knowledge of these PTMs and highlight the unexplored modifications that might have played their part in establishing successful infection. The current review provides an understanding of how PTMs execute viral replication and infection dynamics during plant-potyvirid interactions. We highlighted that PTMs linked to CP, NIa-pro, NIb, and VPg are important to specify their host, virulence, overcoming host innate immunity, and most importantly disarming the host of RNA silencing tool of nailing any intruder. The limitations and potential improvements in studying undermined PTMs, including acetylation, glycosylation, methylation, and neddylation, as well as challenges and future perspectives of this inevitable process are mechanistically deciphered in the course of plant-virus interactions. This communication opens new avenues for investigating the fundamental mechanisms of virus infection and the development of new antiviral strategies for sustainable disease managements.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127940"},"PeriodicalIF":6.1,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.micres.2024.127958
Alberto Pedrero-Méndez, María Illescas, Enrique Monte, Rosa Hermosa
Woronin bodies are unique organelles in Pezizomycotina fungi that allow hyphae compartmentalization and prevent cytoplasmatic bleeding after mechanical injury. Several studies have related the peroxisomal protein HEX1, the major component of Woronin bodies with other biological processes such as hyphal growth, osmotic stress tolerance and pathogenicity. Trichoderma spp. are plant-beneficial multipurpose biological control agents, and proteomic and transcriptomic studies have shown that HEX1 and its corresponding gene are overrepresented when grown in the presence of fungal cell walls and plant polymers. To further investigate the involvement of hex1 in Trichoderma biology, we generated hex1 deletion transformants using the wheat endophytic strain T. simmonsii T137 as host. Results confirmed that hex1 gene is involved in the prevention of cytoplasmatic bleeding, and also has a role in fungal growth and biocontrol potential against phytopathogenic fungi and oomycetes. The involvement of hex1 in the fungal response to osmotic and oxidative stresses is conditioned by the type of stress and by the nutrient richness of the culture medium. The hex1 deletion also affected the interaction with wheat, but did not affect the plant protective effect of T137 against water stress. Overall, this study shows the implication of HEX1 in a wide range of biological processes necessary for T. simmonsii to deploy its abilities to be used as an agriculturally beneficial fungus.
{"title":"The hex1 gene of Trichoderma simmonsii is involved in stress responses, biocontrol potential and wheat plant growth","authors":"Alberto Pedrero-Méndez, María Illescas, Enrique Monte, Rosa Hermosa","doi":"10.1016/j.micres.2024.127958","DOIUrl":"10.1016/j.micres.2024.127958","url":null,"abstract":"<div><div>Woronin bodies are unique organelles in Pezizomycotina fungi that allow hyphae compartmentalization and prevent cytoplasmatic bleeding after mechanical injury. Several studies have related the peroxisomal protein HEX1, the major component of Woronin bodies with other biological processes such as hyphal growth, osmotic stress tolerance and pathogenicity. <em>Trichoderma</em> spp. are plant-beneficial multipurpose biological control agents, and proteomic and transcriptomic studies have shown that HEX1 and its corresponding gene are overrepresented when grown in the presence of fungal cell walls and plant polymers. To further investigate the involvement of <em>hex1</em> in <em>Trichoderma</em> biology, we generated <em>hex1</em> deletion transformants using the wheat endophytic strain <em>T. simmonsii</em> T137 as host. Results confirmed that <em>hex1</em> gene is involved in the prevention of cytoplasmatic bleeding, and also has a role in fungal growth and biocontrol potential against phytopathogenic fungi and oomycetes. The involvement of <em>hex1</em> in the fungal response to osmotic and oxidative stresses is conditioned by the type of stress and by the nutrient richness of the culture medium. The <em>hex1</em> deletion also affected the interaction with wheat, but did not affect the plant protective effect of T137 against water stress. Overall, this study shows the implication of HEX1 in a wide range of biological processes necessary for <em>T. simmonsii</em> to deploy its abilities to be used as an agriculturally beneficial fungus.</div></div>","PeriodicalId":18564,"journal":{"name":"Microbiological research","volume":"290 ","pages":"Article 127958"},"PeriodicalIF":6.1,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142623828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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