{"title":"Purification and characterization of an extremely thermostable metalloprotease from Geobacillus thermoleovorans HBB208.","authors":"Sezgin Karaman, Kubilay Metin","doi":"10.1007/s10123-025-00710-2","DOIUrl":"10.1007/s10123-025-00710-2","url":null,"abstract":"<p><p>Protease enzymes are widely used in industrial applications, often requiring resistance to alkaline and high-temperature conditions while maintaining activity in organic solvents. Discovering thermotolerant proteases from thermophilic organisms is crucial for such applications. This study aimed to identify a novel thermotolerant protease among 201 thermophilic strains isolated from hot springs in Aydın province. Geobacillus thermoleovorans HBB208 was identified as the most efficient protease producer, exhibiting a 3.1 (D/d) ratio on skim milk agar. The protease purified via ammonium sulfate precipitation, hydrophobic interaction, and ion-exchange chromatography, resulting in a 70.2-fold purification. SDS-PAGE and zymogram analyses confirmed the molecular weight of approximately 33.5 kDa and proteolytic activity. The enzyme showed optimal activity at pH 8.0 and 70 °C, and retained 50% activity after 30 min at 87.3 °C in the presence of 10 mM Ca<sup>2</sup>⁺, indicating remarkable thermostability. Kinetic analysis using casein as substrate yielded a K<sub>m</sub> of 0.11 ± 0.01 mM, k<sub>cat</sub> 27.4 ± 0.77, and 2.4 × 10<sup>5</sup> k<sub>cat</sub>/K<sub>m</sub>. The enzyme was stable in the presence of various organic solvents and detergents and displayed broad substrate specificity. These findings suggest that HBB208pro metalloprotease enzyme is a promising candidate for biotechnological and industrial applications requiring extreme operational conditions.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953897","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":"Differential impacts of various plant growth-promoting and osmotic tolerant bacterial strains on proline and sugar accumulation to enhance stress adaptations in tea plants.","authors":"Paritosh Baruah, Pritirekha Saikia, Jumi Gogoi, Pritom Chowdhury, Sosanka Protim Sandilya, Harisadhan Malakar, Hemanta Saikia, Sangeeta Borchetia","doi":"10.1007/s10123-025-00709-9","DOIUrl":"https://doi.org/10.1007/s10123-025-00709-9","url":null,"abstract":"<p><p>Drought stress poses a severe threat to tea plantations globally, leading to a significant reduction in yields. Use of plant growth-promoting bacteria (PGPB) has emerged as a promising strategy to alleviate the detrimental effects of water stress. This study investigates nine distinct bacterial strains, isolated from a drought-prone region in North-East India, for their plant growth-promoting (PGP) traits and their ability to mitigate osmotic stress. These strains were identified based on morphological characteristics and 16S rRNA molecular analysis. Among them, the strains-Chryseobacterium bernardetii (S<sub>4</sub>), Cytobacillus gottheilii (S<sub>5</sub>), Kitasatospora aureofaciens (S<sub>7</sub>), Kocuria palustris (A), and Brachybacterium rhamnosum (B)-exhibited higher PGP activities under osmotic stress conditions (- 0.19 MPa and - 0.93 MPa induced by PEG-6000). Additionally, K. palustris (A) and B. rhamnosum (B) demonstrate effective adaptation to oxidative stress by reducing proline accumulation and were also found to be catalase (CAT) positive. The effect of these osmotolerant PGPBs was further evaluated on tea seedlings under drought stress. Pot experiments in nursery were conducted with three treatments: a positive control (plants watered frequently), a negative control (no treatment), and eight treatments (T1-T8: bacterial inoculations). When comparing the efficacy of bacterial isolates and delivery methods-bioencapsulation and soil drenching. Treatment T6 (comprising strains S<sub>4</sub>, S<sub>5</sub>, S<sub>7</sub>, A, and B) inoculation via soil drenching method improved drought tolerance by effectively modulating osmolyte concentrations, as evidenced by a reduction in total soluble sugars compared to the negative control, highlighting their potential role as bioformulation enhancing osmotolerance and alleviating drought stress in tea plants.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953935","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":"Analysis of variations in cell envelope subproteome and cell length in Acinetobacter baumannii ATCC 19606<sup>T</sup> populations by effect of temperature and desiccation.","authors":"Maite Orruño, Zaloa Bravo, Iciar Martinez, Inés Arana","doi":"10.1007/s10123-025-00706-y","DOIUrl":"https://doi.org/10.1007/s10123-025-00706-y","url":null,"abstract":"<p><p>Acinetobacter baumannii, a pathogen for humans and animals, possesses a tremendous potential to survive under hostile conditions. We studied the effect of temperature, nutrient deprivation, and desiccation on the survival of A. baumannii ATCC 19606<sup>T</sup> by monitoring variations in cellular counts and in cell length and analyzing cell envelope subproteome during the survival process. Nutrient deprivation alone does not appear to have a negative effect on A. baumannii survival, but incubation at 37 °C in an aqueous solution provoked loss of culturability, as well as a marked increase in cell length. Although a high stability of the membrane subproteome was observed, even under environmental conditions that promote morphological changes and loss of culturability, the expression of some membrane proteins did change upon exposure to the stress. Signal peptidase I and fimbrial protein became undetectable in almost all the conditions examined, while EF-Tu (in all conditions) and MinD (in populations incubated at 37 °C) were overexpressed. The great capacity for survival displayed by A. baumannii under adverse conditions may be explained, at least in part, by its capacity to maintain the expression levels of most of its cell envelope proteins and regulate a few others.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953971","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}
Alberto Gonçalves Evangelista, Lucas Dos Santos Janotto, Adriana Paula Possamai, Carolina Cini Perry, Francine Lemes Ribeiro, Fernando Bittencourt Luciano
{"title":"Cross-resistance between halquinol and antibiotics of importance in human and animal health.","authors":"Alberto Gonçalves Evangelista, Lucas Dos Santos Janotto, Adriana Paula Possamai, Carolina Cini Perry, Francine Lemes Ribeiro, Fernando Bittencourt Luciano","doi":"10.1007/s10123-025-00707-x","DOIUrl":"https://doi.org/10.1007/s10123-025-00707-x","url":null,"abstract":"<p><p>The objective of this research was to assess whether halquinol, a zootechnical antimicrobial, can lead to cross-resistance to antibiotics of importance in human and animal health. The minimum inhibitory and bactericidal concentrations of halquinol against 37 Salmonella and Escherichia coli strains/isolates were determined, along with their resistance profiles against 14 antibiotics used in human and veterinary medicine. Sublethal exposure to halquinol was performed to evaluate the acquisition of resistance to the compound by determining new minimum inhibitory and bactericidal concentrations. Cross-resistance to other antibiotics was examined by establishing a new resistance profile after sublethal exposure and comparing it with the previous results. Resistance to halquinol was successfully induced; prior to sublethal exposure, concentrations ranging from 18.25 to 300 µg/mL were required for bacterial inhibition, whereas following sublethal exposure, these values increased to 75 to 1200 µg/mL. The induction of halquinol resistance also impacted resistance to human and veterinary antibiotics. For example, before sublethal exposure to halquinol, 71.4% of Salmonella isolates were resistant to cephalexin; after sublethal exposure, 100% of the isolates exhibited resistance. In E. coli, the percentage of azithromycin-resistant isolates increased from 66.7 to 100% following sublethal exposure. These findings indicate that halquinol, in addition to inducing resistance to itself, may also promote resistance to essential drugs in both human and veterinary medicine. Further studies, particularly molecular investigations, are necessary for a comprehensive characterization of the observed in vitro effects and to determine whether these findings are replicated in vivo.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144953932","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":"Isolation and characterization of multi-drug-resistant Microbacterium esteraromaticum bacteriophage: assessment of antibacterial efficacy and genomic insights.","authors":"Shenwei Cheng, Hao Wang, Keqiang Zhang, Fuyuan Liu, Xingliang Gao, Lianzhu Du","doi":"10.1007/s10123-025-00703-1","DOIUrl":"https://doi.org/10.1007/s10123-025-00703-1","url":null,"abstract":"<p><p>Microbacterium esteraromaticum, a common bacterium utilized in the degradation of organic pollutants, is prevalently found in the wastewater environments of rural areas. However, the excessive use of antibiotics in recent years has endowed M. esteraromaticum with a broad spectrum of antibiotic resistance, transforming it into a potential high-risk contaminant capable of disseminating antibiotic resistance genes (ARGs) within the environment. Lytic bacteriophages, due to their characteristic ability to lysogenize and specifically target host bacteria, have emerged as potent biocontrol agents. In this study, a specific bacteriophage, CASP3, targeting the multi-drug resistant M. esteraromaticum (MDR-ME), was isolated from a wastewater treatment facility. The assessment of phage CASP3 revealed several noteworthy characteristics, including good tolerance and a targeted effect against multidrug-resistant MDR-ME. Studies observed that CASP3, to some extent, reduced the ARGs carried by its host. Furthermore, it demonstrated good environmental compatibility, with no significant potential risks identified. The successful isolation of CASP3 not only provides a new addition to phage resources targeting this bacterium but also offers a potential biocontrol tool for mitigating ARG dissemination and reducing public health risks in rural areas.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144799062","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":"Screening and identification of beneficial soil bacteria: evaluating inoculation effects on plant growth with and without organic matter.","authors":"Shokufeh Moradi, Mohammad Reza Sarikhani","doi":"10.1007/s10123-025-00704-0","DOIUrl":"https://doi.org/10.1007/s10123-025-00704-0","url":null,"abstract":"<p><p>Plant growth-promoting bacteria (PGPB) play a vital role in enhancing crop productivity by improving nutrient availability, phytohormone production, and stress tolerance. While the individual effects of PGPB and organic matter on plant growth are well-documented, their combined influence remains less explored. This research aimed to investigate the effects of certain plant growth-promoting bacteria belonging to different genera on the growth of Corn when organic matter was added to the soil. Plant growth-promoting properties were measured using conventional methods, and the highest phosphate solubility (42.46 mg/L) and auxin production (3.36 mg/L) were observed in isolate Bacillus 2MDP-10, while the highest release of potassium was measured in isolate Azotobacter 3MDP-4 (6.73 mg/L). A greenhouse experiment was conducted using a factorial, completely randomized design. Results indicated that all measured growth parameters, including fresh and dry weight of roots and shoots, plant height, stem diameter, and chlorophyll index, were significantly higher in inoculated treatments compared to the non-inoculated treatment (negative control). Ensifer sp. 3MDP-1 improved Corn growth more effectively than the positive control. This isolate resulted in a 2.8-fold increase in shoot dry weight, a 2.4-fold increase in root dry weight, a 29% increase in plant height, and a 2.4-fold increase in chlorophyll index relative to the negative control. Our results demonstrated that the addition of organic matter in the form of manure significantly enhanced all measured parameters; however, no significant interaction was observed between manure addition and bacterial inoculation, except for root dry weight and nitrogen percentage. It is likely that bacterial colonization in the rhizosphere and the utilization of carbon released by the roots are key factors responsible for this response.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144799063","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":"Altered cell length in deletion mutants of the different divIVA genes in Rhodococcus erythropolis PR4.","authors":"Shabnam Parwin, Preeti Srivastava","doi":"10.1007/s10123-025-00702-2","DOIUrl":"https://doi.org/10.1007/s10123-025-00702-2","url":null,"abstract":"<p><p>Unlike other Actinobacteria, Rhodococcus erythropolis PR4 contains three different copies of divIVA genes. The three divIVA genes show about 22-38% similarity with each other. Deletion mutants of the divIVA genes resulted in altered morphology: elongated cells in △divIVA-2 and short rod-shaped cells in △divIVA-1 and △divIVA-3. The expression of the divIVA-2 gene was found to be higher as compared to the divIVA-1 and divIVA-3 genes in wild-type cells. The subcellular localisation studies revealed that the three different DivIVA proteins are spatially present at different regions of cell space. Our results suggest that an interplay of the three DivIVA proteins plays a role in cell shape maintenance in R. erythropolis PR4. Bioinformatics analysis and interactome study show that amongst the three copies of divIVA genes, the second copy, i.e., divIVA-2 gene, might have a more governing function in the cell division process as compared to the other two copies.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144799061","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}
Zhi Lin Chen, Hong Zhi Du, Jian Ke Wang, Chang Lin, Shan Shan Liang, Wei Wei Ze, Chong Xin Yue, Ting Ting Feng, Wei Li
{"title":"Microbial community variation enhances active compound composition in Salvia miltiorrhiza.","authors":"Zhi Lin Chen, Hong Zhi Du, Jian Ke Wang, Chang Lin, Shan Shan Liang, Wei Wei Ze, Chong Xin Yue, Ting Ting Feng, Wei Li","doi":"10.1007/s10123-025-00700-4","DOIUrl":"https://doi.org/10.1007/s10123-025-00700-4","url":null,"abstract":"<p><p>Salvia miltiorrhiza is a widely used medicinal plant, and post-harvest processing methods such as sweating may influence its metabolite composition and microbial interactions. However, the metabolic and microbial changes induced by sweating remain poorly understood. This study aimed to investigate how sweating affects the metabolite profile of S. miltiorrhiza and its associated bacterial communities, with a focus on identifying key metabolic shifts and microbial dynamics. Widely targeted metabolomics was employed to compare the composition and relative content of metabolites between control (non-sweated) and sweated S. miltiorrhiza plants. Additionally, high-throughput sequencing was used to analyze variations in bacterial communities at different sweating stages. A total of 435 differentially present metabolites were identified, categorized into 11 classes, with quinones, phenolic acids, and lipids being the most prominent. Sweating significantly increased microbial diversity and richness, and we established a correlation between the accumulation of quinones and phenolic acids and shifts in bacterial community structure. Notably, sweating enhanced the levels of key metabolites, which in turn promoted the relative abundance of potentially beneficial microorganisms. Furthermore, distinct bacterial populations at different sweating stages contributed to the unique quality traits of S. miltiorrhiza. The findings demonstrate that sweating not only alters the metabolite profile of S. miltiorrhiza but also shapes its associated bacterial communities, leading to improved accumulation of bioactive compounds.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144794379","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}
Brianda Karina Félix-Sicairos, Rita Elizabeth Martínez Martínez, Eleazar Samuel Kolosovas-Machuca, Jaime Ruiz-García, Alex Mira, José Luis Cuellar Camacho, Saray Aranda Romo
{"title":"Differential susceptibility of Streptococcus dentisani to dental surfaces: An atomic force microscopy study.","authors":"Brianda Karina Félix-Sicairos, Rita Elizabeth Martínez Martínez, Eleazar Samuel Kolosovas-Machuca, Jaime Ruiz-García, Alex Mira, José Luis Cuellar Camacho, Saray Aranda Romo","doi":"10.1007/s10123-025-00696-x","DOIUrl":"https://doi.org/10.1007/s10123-025-00696-x","url":null,"abstract":"<p><strong>Background: </strong>Given frequent dental restorations, understanding the interactions of probiotic Streptococcus dentisani with enamel and dental materials is key, in contrast to the well-studied Streptococcus mutans. This knowledge is vital for the potential applications in promoting oral health of S. dentisani.</p><p><strong>Objective: </strong>This study aims to evaluate and compare S. mutans and S. dentisani initial adhesion, proliferation, and colonization on dental enamel and commonly used dental materials: nickel-chromium alloy, porcelain, lithium disilicate, autocured, and thermocured acrylics, using atomic force microscopy (AFM).</p><p><strong>Methods: </strong>The study utilized S. mutans ATCC 35665 and S. dentisani CECT 7746 cultured in brain-heart infusion (BHI) broth. The dental substrates used consisted of enamel obtained from healthy unerupted third molars, nickel-chromium alloy (Ni-Cr), porcelain, lithium disilicate, and both autocured and thermocured acrylics. All simples were cut into 1 cm pieces and subsequently mounted for the AFM analysis. Bacterial suspensions were incubated on these surfaces for 24 h. Surface topography and bacterial adhesion, proliferation, and colonization were analyzed using AFM in contact mode. Roughness parameters (R<sub>a</sub>, R<sub>rms</sub>, R<sub>Max</sub>) were quantified from AFM images using the Nanoscope analysis software.</p><p><strong>Results: </strong>Atomic force microscopy analysis revealed that after a 24-h incubation, S. mutans demonstrated a superior capacity to adhere, proliferate, and colonize all tested substrates compared to S. dentisani. Streptococcus dentisani was found to be more susceptible to the bactericidal effects of the materials. Notably, porcelain and lithium disilicate surfaces exhibited strong antimicrobial activity. On porcelain, no intact S. dentisani cells were observed, only bacterial debris. Similarly, lithium disilicate showed evidence of bacterial decomposition for both strains, suggesting a potent bactericidal effect.</p><p><strong>Conclusion: </strong>For the first time, our data revealed that S. dentisani exhibited a reduced capacity for dental surface adhesion, proliferation, and colonization across all tested substrates, compared to S. mutans.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144784287","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}
Jeanett Daga-Quisbert, Daniela Mendieta, Gunaratna Kuttuva Rajarao, Antonius J A van Maris, Jorge Quillaguamán
{"title":"Production of ectoine by Vreelandella boliviensis using non-aseptic repeated-batch and continuous cultivations in an air-lift bioreactor.","authors":"Jeanett Daga-Quisbert, Daniela Mendieta, Gunaratna Kuttuva Rajarao, Antonius J A van Maris, Jorge Quillaguamán","doi":"10.1007/s10123-024-00626-3","DOIUrl":"10.1007/s10123-024-00626-3","url":null,"abstract":"<p><p>Ectoine, an osmolyte produced by various microorganisms, has numerous commercial applications. Vreelandella boliviensis (formerly called Halomonas boliviensis) generates high ectoine concentrations, i.e., 78.6 g/L. This study investigated three cultivation strategies for ectoine production in a non-aseptic air-lift bioreactor. The first strategy was performed in a repeated-batch mode with 5% (w/v) NaCl to induce cell growth, followed by the addition of solid NaCl to a final concentration of 12.5% (w/v) to prompt ectoine production. A maximum dry cell weight of 13.8 g/L at 46.5 h, a maximum ectoine concentration of 1.37 g/L at 37.5 h, and a maximum volumetric productivity of 0.93 g/L/d at 34.5 h were reached. The second strategy employed a three-step repeated-batch cultivation method. In the first step, cells were grown at the optimum salt concentration, harvested by centrifugation, and cultivated in a replenished medium for the second step. In the third step, the cells were harvested again and grown in a fresh medium containing 12.5% (w/v) NaCl. This strategy improved dry cell weight to 32 g/L, ectoine concentration to 4.37 g/L, and productivity to 1.76 g/L/day at 60 h of cultivation. The third strategy consisted of continuous cultivations that were investigated using different NaCl concentrations. The highest ectoine concentration of 2.83 g/L and productivity of 3.49 g/L/d were obtained with 8.5% (w/v) NaCl at a dilution rate of 0.05 (1/h). This study is the first to report ectoine production by V. boliviensis in continuous air-lift bioreactors under non-aseptic conditions.</p>","PeriodicalId":14318,"journal":{"name":"International Microbiology","volume":" ","pages":"1385-1394"},"PeriodicalIF":2.3,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142893696","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}