CHEMOSPHERE
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2021
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IF 7.086
Xiaoning Li,Hailong Liu,Weiben Yang,Hongjie Sheng,Fang Wang,Jean Damascene Harindintwali,H.M.S.K. Herath,Yinping Zhang
The search for nature-based tools to enhance bioremediation is essential for the sustainable restoration of contaminated ecosystems. Humic acid (HA) is an important component of organic matter in soil and water, but its effect on the microbial degradation of organic pollutants remains unclear. In this study, the biodegradation of pyrene by Mycobacterium sp. NJS-1 with and without HA was investigated. Only around 10.5% of pyrene was biodegraded in the pyrene treatment alone, whereas the addition of HA significantly enhanced biodegradation to the point where over 90% of pyrene was biodegraded. The production of 4,5-dihydropyrene-4,5-diol and phenanthrene-3,4-diol indicated the metabolic pathway via attacking of 4,5-positions of pyrene. Interestingly, 1,2-dimethoxypyrene was detected with the addition of HA, suggesting that HA induced a new ring-opening pathway involving the attack on the 1,2-positions of pyrene. The addition of HA first induced protein self-cleavage behavior with a significant increase in phenylalanine , tyrosine, and tryptophan containing large numbers of COO − groups. Furthermore, it altered the intracellular and extracellular ultrastructure of bacterial cells, promoting their growth in size and number as well as reducing the space between them. Overall, HA increased the ring-opening positions of pyrene and facilitated its interaction with bacterial cells, thus improving its biodegradability . Building upon the findings of this study to further research is conducive to the sustainable solution of environmental pollution .
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
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2018
·Vol. 186
·期 2
·496-506
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IF 1.797
Zhou Pei,Fang Ya-kun,Yao Hao-ke,Li Hua,Wang Gang,Liu Yu-peng
In this study, a method for the efficient production of dehydroepiandrosterone (DHEA) from phytosterols in a vegetable oil/aqueous two-phase system by Mycobacterium sp . was developed. After the 3-hydroxyl group of phytosterols was protected, they could be converted into DHEA with high yield and productivity by Mycobacterium sp . NRRL B-3683. In a shake flask biotransformation, 15.05 g l −1 of DHEA and a DHEA yield of 85.39% (mol mol −1 ) were attained after 7 days with an initial substrate concentration of 25 g l −1 . When biotransformation was carried out in a 30-l stirred bioreactor with 25 g l −1 substrate, the DHEA concentration and yield was 16.33 g l −1 and 92.65% (mol mol −1 ) after 7 days, respectively. The results of this study suggest that inexpensive phytosterols could be utilized for the efficient production of DHEA.
研究领域:
微生物学
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生物化学
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制药工程
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PubMed
高影响因子
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
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2025
·Vol. 69
·期 5
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IF 4.5
Pusheng Xu,Yi Li,Bihan Xu,Dan Cao,Xu Dong,Yanghui Xiang,Xiuzhi Jiang,Xin Yuan,Yuwei Qiu,Ying Zhang
Mycobacterium abscessus is a fast-growing nontuberculous mycobacterium that can cause severe disease and poses a significant challenge for clinical management. New drugs are urgently needed for more effective treatment. Nitroxoline, an antibiotic used for treating urinary tract infections in Europe, has recently been shown to have promising activity against M. abscessus. However, the mechanism of its modified activity is not known. In anticipation for its potential clinical use, in this study, we investigated the mechanism of nitroxoline activity modification through mutant selection followed by whole-genome sequencing. We identified mutations in a transcriptional repressor MarR (MAB_2648c) controlling the expression of efflux pumps MmpS5-MmpL5 family that are associated with nitroxoline activity modification. Complementation of the mutants with the wild-type marR gene restored the MIC values to levels comparable to those of the wild-type strain. This study elucidates the key mechanism of how M. abscessus mutations modify the activity of nitroxoline, which has significant implications for rapid molecular detection of drug-resistant M. abscessus and for further studies on resistance mechanisms.
研究领域:
微生物学
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药理学
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分子生物学
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PubMed
高影响因子
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
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2025
·Vol. 41
·期 5
·1-10
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IF 4.2
Bi Yingjing,Han Yun,Bi Yanlan,Zhang Linshang,Sun Shangde
Sterol esters are naturally present in the by-product of edible oil processing, which is generally converted to sterols through saponification. Steroid intermediates play a crucial role in the production of pharmaceuticals, and these intermediates are predominantly synthesized via fermentation of sterol. This research explored the direct conversion of sterol esters into steroid intermediates using Mycobacterium sp. as a fermentation agent. The results demonstrated the successful identification of four steroid intermediates: androstenedione, 1,4-androstadienedione, 22-hydroxy-23,24-bisnorchol-4-ene-3-one, and 22-hydroxy-23,24-bisnorchol-1,4-dien-3-one, their individual intermediate concentrations were as follows: 144.2, 176.2, 30.8, 53.6 mg/L, with a total yield of 404.8 mg/L and a conversion rate of 29.5%. The optimized fermentation conditions included soybean oil at 3%, an initial pH of 7.0, a nitrogen source of 4.5 g/L, and hydroxypropyl-β-cyclodextrin of 15.0 g/L. Proteomic analysis revealed that sterol esters conversion pathway mirrors that of sterol, with an additional hydrolysis process. This work significantly expands our understanding of steroid intermediates production and offers valuable insights for the bioproduction industry. Graphical
研究领域:
生物化学
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制药工程
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微生物学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Na Li,Rui Liu,Jianjun Chen,Jian Wang,Liqun Hou,Yuemei Zhou
This study investigated Fire Phoenix ( Festuca L.) and Echinacea purpurea (L.) Moench inoculated with a Mycobacterium strain N12 in remediation of soils contaminated with both polycyclic aromatic hydrocarbons (PAHs) and cadmium (Cd). Plant growth and PAH and Cd removal were monitored in 60, 120, and 150 days after transplanting. Results showed that Fire Phoenix plants grown in soil containing 200 mg/kg PAHs and 15 mg/kg Cd inoculated with N12 were able to remove 76.3% PAHs compared to removal of 68.3% of PAHs by the plants without N12 inoculation. On day 150, the underground biomass of Fire Phoenix plants grown in soil inoculated with N12 increased 59.40% compared to that without N12 inoculation. The enhanced removal of PAH by Fire Phoenix and N12 was related to the improved rhizosphere microbial activities . However, inoculation of N12 to E. purpurea grown soil did not significantly improve the removal of PAHs and Cd. Our results showed that phytoremediation of PAHs and Cd can be enhanced by a Mycobacterium strain N12, especially when PLFA concentrations of bacteria and fungi exceeded 60% of the initial concentrations, but the enhancement is plant species dependent.
研究领域:
环境科学
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微生物学
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植物学
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DOI
PubMed
高影响因子
Microorganisms
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2025
·Vol. 13
·期 5
·1171
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IF 4.2
Shuyun Li,Jiazhen Liu,Ping Fang
The development of efficient bioremediation technologies for polycyclic aromatic hydrocarbons contamination is a hot research topic in the environmental field. In this study, we found that theMycobacteriumsp., TJFP1, has the function of degrading low molecular weight PAHs, and further investigated its degradation characteristics using the PAH model compound phenanthrene as a target pollutant. The optimal growth and degradation conditions were determined by single-factor experiments to be 37 °C, pH 9.0, and an initial concentration of 100 mg/L phenanthrene. Under this condition, the degradation efficiency of phenanthrene reached 100% after 106 h of incubation, and the average degradation rate could reach 24.48 mg/L/day. Combined with whole genome sequencing analysis, it was revealed that its genome carries a more complete phenanthrene degradation pathway, including functional gene clusters related to the metabolism of PAHs, such as phd and nid. Meanwhile, intermediates such as phthalic acid were detected; it was determined that TJFP1 metabolizes phenanthrene via the phthalic acid pathway. Simulated contaminated soil experiments were also conducted, and the results showed that the removal rate of phenanthrene from the soil after 20 days of inoculation with the bacterial strain was about 3.7 times higher than that of the control group (natural remediation). At the same time from the soil physical and chemical properties and soil microbial community structure of two levels to explore the changes in different means of remediation, indicating that it can be successfully colonized in the soil, and as a dominant group of bacteria to play the function of remediation, verifying the environmental remediation function of the strains, for the actual inter-soil remediation to provide theoretical evidence. This study provides efficient strain resources for the bioremediation of PAH contamination.
研究领域:
环境科学
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微生物学
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基因组学
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PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2018
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IF 6.434
Shanshan Sun,Haizhen Wang,Yuanzhi Chen,Jun Lou,Laosheng Wu,Jianming Xu
Mycobacterium sp. WY10 was a highly effective PAHs-degrading bacterium that can degrade phenanthrene (PHE, 100 mg L −1 ) completely within 60 h and 83% of pyrene (PYR, 50 mg L -1 ) in 72 h. In this study, ten and eleven metabolites, respectively, were identified in PHE and PYR degradation cultures, and a detailed PHE and PYR metabolism maps were constructed based on the metabolic results. The strain WY10 degraded PHE and PYR with initial dioxygenation mainly on 3,4- and 4,5-carbon positions, respectively. Thereafter, PYR degradation entered the PHE degradation pathway via the ortho -cleavage. It was observed that the “lower pathway” of PHE and PYR degradations were different. Based on the kinetics of residual metabolites, PHE was degraded in a dominant phthalate pathway and a minor salicylate pathway. However, both phthalate and salicylate pathways played important roles on PYR degradation. The WY10 genome revealed there were fifty-three genes related to PAHs degradations, including a complete gene set for PHE and PYR degradation via the phthalate pathway. The candidate gene/ORF, BOH72_19755, encoding salicylate synthase might contribute in the salicylate pathway.
研究领域:
环境微生物学
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分子生物学
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DOI
PubMed
高影响因子
BMC Complementary Medicine and Therapies
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2025
·Vol. 25
·期 1
·1-10
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IF 3.4
Jiang Xiuzhi,Cao Dan,Xu Bihan,Yuan Xin,Xiang Yanghui,Wu Tiantian,Zhang Ying
Background Mycobacterium intracellulare ( M. intracellulare ) is a common, slow-growing opportunistic pathogen that can cause chronic pulmonary and extrapulmonary infections. Despite its rising incidence, standard treatments are often ineffective in eradicating M. intracellulare , leading to prolonged treatment and high recurrence rates, likely due to persistence of non-growing bacteria. Although essential oils are known for their antimicrobial properties, their effects on M. intracellulare , particularly in its non-growing phase, have not been well studied. Methods We screened 151 essential oils to assess their antimicrobial activity against stationary-phase non-growing M. intracellulare . Essential oils with significant activity were further evaluated at different concentrations by MIC and drug exposure tests. Results Thirty-four essential oils were found to have activity at 5000 µg/mL, with 18 showing effectiveness at 1250 µg/mL. Six essential oils, Ajwain, Oregano, Palmarosa, Thyme, Mountain Savory, and Litsea Cubeba had the highest activity, achieving 100% bacterial clearance after one day exposure. Carvacrol, the key active component of Ajwain, Oregano, Thyme, Mountain Savory, eradicated stationary-phase bacteria at 310 µg/mL concentration within one day, while citronellol, the active component of Palmarosa, at 630 µg/mL achieved complete clearance after three day exposure. Conclusions We have newly identified several essential oils, including Ajwain, Oregano, Thyme, Mountain Savory, Palmarosa, and Litsea Cubeba and their active components such as carvacrol and citronellol, to have promising activity against M. intracellulare, and these findings may have implications for developing improved treatments for M. intracellulare infections.
研究领域:
微生物学
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药理学
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PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
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IF 5.7
Qi Han,Youwen Xing,Lulu Yan,Lulu Cao,Zehao Li,Jiandong Jiang,Xihui Xu,Chen Chen
Cyromazine, a triazine insecticide, raises food safety concerns due to residues in vegetables like cowpeas. Microbial metabolism is key for pesticide elimination, but bacteria efficient in cyromazine degradation are limited, with uncharacterized enzymes. This study isolated a highly efficient cyromazine-degrading bacterium, Mycobacterium sp. M15, from a cowpea field. M15 utilized cyromazine as the sole carbon source for its growth and completely degraded 0.5 mM cyromazine within 24 h. The degradation pathway involved hydrolyzing cyromazine to N-cyclopropylammeline and further to N-cyclopropylammelide, with amino groups removed sequentially. The cyclopropylamine group in N-cyclopropionamide continued to hydrolyze to cyanuric acid. A protein, CriA, identified as an aminohydrolase in M15, degraded cyromazine to N-cyclopropylammeline. Using CriA reduced cyromazine residues on cowpea surfaces and completely degraded them in immersion solutions. These findings offer insights into cyromazine’s microbial degradation mechanism and highlight the potential of cyromazine-degrading enzymes in enhancing food safety.
研究领域:
环境科学
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微生物学
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生物技术
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农药化学
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DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
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2023
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IF 4.4
Xinxin Wang,Xia Ke,Ximan Zhao,Qijie Ren,Jiahao Cui,Zhiqiang Liu,Yuguo Zheng
Understanding the mycobacteria degradation of sterol may facilitate strategies for the directed biotransformation of steroidal drug intermediates. Due to the long and complicated catabolic process, several key steps that involved in the C-C bond cleavage of steroidal side-chain remain unknown. In the present study, an aldolase SalA from Mycobacterium neoaurum was identified that was related to the synthesis of 3-oxo-4-pregnene-20-carboxyl aldehyde and 20-hydroxymethyl pregn-4-ene-3-one (4-HBC). As a member of the thiolase superfamily, the aldolase SalA-SalB is composed of a thiolase-like protein (SalA) and a DUF35 domain (SalB). As a result, the gene salA was determined that had special significance for the synthesis of 4-HBC in sterol metabolism by performing knockout and replenishment. Based on insights provided by the docking model and mutants analysis, the hypothesis of the catalytic mechanism was proposed. Furthermore, the deletion of salA absolutely eliminated the by-product 4-HBC and meanwhile the molar yield of ADD was increased by 10 %. The dominant role of SalA in the C24 steroidal side-chain cleavage as confirmed in this study provided a further clarification on the phytosterol degrading pathway in Mycobacterium neoaurum , which is of significant importance for the directed biotransformation between C19- and C22-steroids.
研究领域:
微生物学
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生物化学
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药物生物转化
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DOI
高影响因子
Nature Communications
·
2021
·Vol. 12
·期 1
·1-14
·
IF 14.919
Wang Yuqin,Guan Xiaoyu,Zhang Shanyu,Liu Yao,Wang Sha,Fan Pingping,Du Xiaoyu,Yan Shuanghong,Zhang Panke,Chen Hong-Yuan,Li Wenfei,Zhang Daoqiang,Huang Shuo
Folding of RNA can produce elaborate tertiary structures, corresponding to their diverse roles in the regulation of biological activities. Direct observation of RNA structures at high resolution in their native form however remains a challenge. The large vestibule and the narrow constriction of a Mycobacterium smegmatis porin A (MspA) suggests a sensing mode called nanopore trapping/translocation, which clearly distinguishes between microRNA, small interfering RNA (siRNA), transfer RNA (tRNA) and 5 S ribosomal RNA (rRNA). To further profit from the acquired event characteristics, a custom machine learning algorithm is developed. Events from measurements with a mixture of RNA analytes can be automatically classified, reporting a general accuracy of ~93.4%. tRNAs, which possess a unique tertiary structure, report a highly distinguishable sensing feature, different from all other RNA types tested in this study. With this strategy, tRNAs from different sources are measured and a high structural conservation across different species is observed in single molecule.
研究领域:
纳米技术
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生物物理学
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生物信息学
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分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Frontiers in Cellular and Infection Microbiology
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2023
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IF 5.7
Shan. Gao,Wenjuan. Nie,Lina. Liu,Lei. Su,Yingxia. You,Ruixue. Geng,Naihui Chu
Objective To evaluate contezolid (MRX-I) antibacterial activity against Mycobacterium abscessus in vitro and in vivo and to assess whether MRX-I treatment can prolong survival of infected zebrafish. Methods MRX-I inhibitory activity against M. abscessus in vitro was assessed by injecting MRX-I into zebrafish infected with green fluorescent protein-labelled M. abscessus . Thereafter, infected zebrafish were treated with azithromycin (AZM), linezolid (LZD) or MRX-I then maximum tolerated concentrations (MTCs) of drugs were determined based on M. abscessus growth inhibition using one-way ANOVA. Linear trend analysis of CFU counts and fluorescence intensities (mean ± SE values) was performed to detect linear relationships between MRX-I, AZM and LZD concentrations and these parameters. Results MRX-I anti- M. abscessus minimum inhibitory concentration (MIC) and MTC were 16 μg/mL and 15.6 μg/mL, respectively. MRX-I MTC-treated zebrafish fluorescence intensities were significantly lower than respective LZD group intensities (whole-body: 439040 ± 3647 vs. 509184 ± 23064, p < 0.01); head: 74147 ± 2175 vs. 95996 ± 8054, p < 0.05). As MRX-I concentration was increased from 0.488 μg/mL to 15.6 μg/mL, zebrafish whole-body, head and heart fluorescence intensities decreased. Statistically insignificant differences between the MRX-I MTC group survival rate (78.33%) vs. corresponding rates of the 62.5 μg/mL-treated AZM MTC group (88.33%, p > 0.05) and the 15.6 μg/mL-treated LZD MTC group (76.67%, p > 0.05) were observed. Conclusion MRX-I effectively inhibited M. abscessus growth and prolonged zebrafish survival when administered to M. abscessus -infected zebrafish, thus demonstrating that MRX-I holds promise as a clinical treatment for human M. abscessus infections.
研究领域:
微生物学
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药理学
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传染病
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斑马鱼模型
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）