BIORESOURCE TECHNOLOGY
·
2024
·
IF 9.7
Juan Huang,Alei Zhang,Qi Yang,Yajun Ding,Zhongliang Xiao
The explosive and biorefractory nature of nitrocellulose (NC) poses major risks to both humans and the environment. Expanding the range of microorganisms capable of degrading NC is essential, though the most effective known microorganisms, Desulfovibrio genera and Fusarium solani , achieve degradation rates of 5%-25%. Here, a novel strain, Rhodococcus pyridinivorans LZ1 was isolated, demonstrating the ability to degrade NC, with its growth potentially enhanced by the presence of NC. The degradation process was monitored by assessing changes in nitrate, nitrite, and ammonium. Notably, the –OH strength of NC increased over time, whereas the energetic functional groups (–NO 2 and O-NO 2 ) diminished. Furthermore, the presence of NC enhanced nitrate esterase activity 1–2-fold, indicating that ammonification was the primary pathway for NC biodegradation. By converting the nitrate ester of NC into hydroxyl, R. pyridinivorans LZ1 mitigates the harmful effects of NC, offering a promising approach for the treatment of NC waste and wastewater.
研究领域:
微生物学
·
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Communications Biology
·
2023
·Vol. 6
·期 1
·1-13
·
IF 5.9
Guo Wenbin,Duan Jingjing,Shi Zhengguang,Yu Xue,Shao Zongze
Evidence for microbial biodegradation of polyethylene terephthalate (PET) has been reported, but little is known about the PET biodegradation process and molecular mechanism by marine microorganisms. Here, we show the biodegradation of PET by the membrane-anchored PET esterase from the marine bacterium Rhodococcus pyridinivorans P23, elucidate the properties of this enzyme, and propose the PET biodegradation by this strain in biofilm. We identify the PET-degrading enzyme dubbed PET esterase through activity tracking. In addition to depolymerizing PET, it hydrolyzes MHET into TPA under acid conditions. We prove that it is a low and constitutively transcribed, membrane-anchored protein displayed on the cell surface. Furthermore, we also investigate the microbial groups possessing PET esterase coupled with the TPA degradation pathway, mainly in the phyla Proteobacteria and Actinobacteriota . Clarification of the microbial PET biodegradation in the marine environment will contribute to the understanding of bioremediation of marine PET pollution.
研究领域:
环境微生物学
·
生物技术
·
海洋污染
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Fermentation-Basel
·
2023
·Vol. 9
·期 2
·133
·
IF 3.7
Peng Cheng,Muhammad Usman,Muhammad Arslan,Huanqing Sun,Li Zhou,Mohamed Gamal El-Din
A Gram-positive exoelectrogenRhodococcus pyridinivoranssp. strain HR-1 was cultivated from leachate-fed microbial fuel cell (MFC) to study the biodegradation effect of pyridine. In the comparison with mixed cultured MFC, HR-1 presented a remarkable electrical capacity with a maximum output of 4.33 W/m3under 30 °C in neutral anolyte with 1 g/L acetate as a substrate. Further, HR-1 demonstrated the environmental resistance as a Gram-positive strain. Microbial metabolism was evident at pH between 5–9 and temperature in the range of 20–40 °C, whereas optimal condition for pyridine degradation was observed at 30 °C. This is the first study reporting the degradation of pyridine in the bio-electrochemical system that achieved a 42% ± 5% degradation rate in a full operation cycle at 2 g/L of the concentration. Considering the nonnegligible internal resistance of HR-1-inoculated MFC, trehalose lipid was also introduced as a bio-surfactant to reduce the charge transfer obstacle between the microbes and the electrodes. The surface morphology illustrated that the strain had a plump shape with a high specific area. Accordingly, bio-surfactant addition promoted the anode biomass (1.2 ± 0.1 mg/cm2to 1.7 ± 0.2 mg/cm2) and achieved a higher degradation rate (68% ± 4%). The feasibility of electrochemical disposal on pyridine and eminent adaptability of strain sp. HR-1 as a Gram-positive exoelectrogen makes MFC a practical approach for real application.Keywords:microbial fuel cells;gram-positive exoelectrogen;pyridine;trehalose lipid;Rhodococcus pyridinivorans
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2022
·
IF 11.889
Peng Cheng,Yingchuan Zhang,Nianfang Ma,Lining Wang,Liqun Jiang,Zhen Fang,Yitong Wang,Xiangping Tan
Microbial fuel cell (MFC) exhibits huge potentials in disposing wastewater and extra energy consumption. Exploring useful microorganisms for MFC is the crucial section. Herein, the electrochemical mechanism of extracellular anaerobic respiration in MFC inoculated with gram-positive Rhodococcus pyridinivorans HR-1, was first revealed. The MFC exhibited rapid recovery of currents on anode, and could recover to maximum output within one hour, with redox peaks near −0.38 and −0.18 V through electron transfer between the biofilm and anode. When the biofilm-based pathway was blocked by wrapping the anode with Millipore filter membrane, HR-1 inoculated MFC could still generate electricity within a longer recovery period (∼35 h) during anolyte exchange. This was proposed as a self-secreted electron shuttle pathway for electron transfer in R. pyridinivorans HR-1. Cyclic voltammetry analysis revealed that the biofilm-based and self-secreted electron shuttle-based pathways co-existed in R. pyridinivorans HR-1 inoculated MFC, which could play synergistic roles in electricity generation.
研究领域:
微生物学
·
环境科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2022
·
IF 7.129
Xiaolei Wang,Hong Lu,Qiansheng Li,Yang Zhou,Jiti Zhou
Anthraquinone compounds (ACs) could be efficiently degraded and detoxified by bacteria. However, the molecular mechanism of bacterial degradation and detoxification of ACs remains unclear. In this study, 1-aminoanthraquinone-2-sulfonate (ASA-2) was used as a model anthraquinone compound, the response mechanism of Rhodococcus pyridinivorans GF3 to ASA-2 using genomics and transcriptomics techniques was investigated. Comparative genome analysis showed that strain GF3 owned an especial gene region (Genes 1337–1399) containing the genes encoding cytochrome P450, monooxygenase, dehydrogenase and oxidoreductase, which did not commonly exist in Rhodococcus genus. The amino acid sequences of these genes were similar to those of the cleavage enzymes of anthraquinone ring in Aspergillus genus. Moreover, the transcriptions of Genes 1392–1394 (cytochrome 450 gene cluster) displayed 1.8–3.1-fold up-regulation under ASA-2 exposure. Meanwhile, as an intermediate product of ASA-2, catechol was degraded to acetyl-CoA, succinyl-CoA and pyruvate, resulting in the enhanced tricarboxylic acid cycle and ATP generation. This process also promoted the up-regulation of the genes encoding resistance, efflux, transporter and anti-oxidation pressure proteins, which were involved in resisting ASA-2 and maintaining the homeostasis of cells. These results provided us with a further understanding of the molecular mechanism of degradation and detoxification of ACs.
研究领域:
微生物学
·
环境科学
·
分子生物学
·
基因组学
·
转录组学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2018
·
IF 4.61
Hai-Ming Zhao,Rui-Wen Hu,Xue-Xue Chen,Xue-Bin Chen,Huixiong Lü,Yan-Wen Li,Hui Li,Ce-Hui Mo,Quan-Ying Cai,Ming-Hung Wong
A novel bacterial strain designated as Rhodococcus pyridinivorans XB, capable of utilizing various endocrine disruptor phthalates or phthalic acid (PA) as sole source of carbon and energy, was isolated from activated sludge. Under the optimal culture conditions (pH 7.08, 30.4 °C, inoculum size (OD 600 nm ) of 0.6) obtained by response surface methodology, di-(2-ethylhexyl) phthalate (DEHP, 200 mg/L) could be degraded by strain XB with a removal rate of 98% within 48 h. Under the observation of an atomic force microscope, it was confirmed that DEHP did not inhibit the growth of strain XB which might produce some extracellular polymeric substances as a response to DEHP stress, resulting in rapid degradation of DEHP. At initial concentrations of 50–800 mg/L DEHP, its degradation curves were well fitted with the first-order kinetic model, and the half-life of DEHP degradation varied from 5.44 to 23.5 h. The degradation intermediates of DEHP were identified by both GC–MS and high performance liquid chromatography–time of flight-mass spectrometry (HPLC–TOF-MS). Significant up-regulation was observed for the relative expression levels of genes (i.e., phthalate hydrolase, PA 3,4-dioxygenase, protocatechuate 3,4-α and 3,4-β dioxygenase) involved in DEHP degradation determined by real-time quantitative PCR (RT-qPCR). A DEHP biodegradation pathway by strain XB was proposed based on the identified intermediates and the degrading genes. Bioaugmentation of DEHP-contaminated soils with strain XB could efficiently promote DEHP removal, offering great potential in bioremediation of DEHP-contaminated environment.
研究领域:
环境微生物学
·
生物修复
·
分子生物学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）