BACKGROUND Kidney transplantation is the best option for patients with end-stage renal disease.However,the need for lifelong immunosuppression results in renal transplant recipients being susceptible to various infect...BACKGROUND Kidney transplantation is the best option for patients with end-stage renal disease.However,the need for lifelong immunosuppression results in renal transplant recipients being susceptible to various infections.Rhodococcus equi(R.equi)is a rare opportunistic pathogen in humans,and there are limited reports of infection with R.equi in post-renal transplant recipients and no uniform standard of treat-ment.This article reports on the diagnosis and treatment of a renal transplant recipient infected with R.equi 21 mo postoperatively and summarizes the charac-teristics of infection with R.equi after renal transplantation,along with a detailed review of the literature.Here,we present the case of a 25-year-old man who was infected with R.equi 21 mo after renal transplantation.Although the clinical features at the time of presentation were not specific,chest computed tomography(CT)showed a large volume of pus in the right thoracic cavity and right middle lung atelectasis,and fiberoptic bronchoscopy showed an endobronchial mass in the right middle and lower lobe orifices.Bacterial culture and metagenomic next-generation sequen-cing sequencing of the pus were suggestive of R.equi infection.The immunosup-pressive drugs were immediately suspended and intravenous vancomycin and azithromycin were administered,along with adequate drainage of the abscess.The endobronchial mass was then resected.After the patient’s clinical symptoms and chest CT presentation resolved,he was switched to intravenous ciprofloxacin and azithromycin,followed by oral ciprofloxacin and azithromycin.The patient was re-hospitalized 2 wk after discharge for recurrence of R.equi infection.He recovered after another round of adequate abscess drainage and intravenous ciprofloxacin and azithromycin.CONCLUSION Infection with R.equi in renal transplant recipients is rare and complex,and the clinical presentation lacks specificity.Elaborate antibiotic therapy is required,and adequate abscess drainage and surgical excision are necessary.Given the recurrent nature of R.equi,patients need to be followed-up closely.展开更多
为解决乙草胺残留问题,采用连续传代富集培养的方法,从长期生产乙草胺的农药厂污染土壤中分离筛选到1株乙草胺降解菌株AC-1。经过形态学特征、生理生化特征和16S rRNA基因序列系统发育分析,菌株AC-1被鉴定为红球菌属(Rhodococcus)。菌株...为解决乙草胺残留问题,采用连续传代富集培养的方法,从长期生产乙草胺的农药厂污染土壤中分离筛选到1株乙草胺降解菌株AC-1。经过形态学特征、生理生化特征和16S rRNA基因序列系统发育分析,菌株AC-1被鉴定为红球菌属(Rhodococcus)。菌株AC-1在48h内能将0.2 m M的乙草胺完全降解,但不能矿化乙草胺。借助LC-MS,确定乙草胺降解终产物为2-氯-N-(2-乙基-6-甲基苯基)乙酰胺(CMEPA)。菌株AC-1降解乙草胺的最适温度为30℃,最适p H值为7.5。0.1 m M的Cu2+和Hg2+对菌株AC-1降解乙草胺具有很强的抑制作用,而0.1 m M的Fe2+则对菌株AC-1降解乙草胺具有微弱的促进作用。菌株AC-1对乙草胺的降解效果与起始接种量呈正相关。菌株AC-1对甲草胺和丁草胺表现出良好的降解效果,但对异丙甲草胺的降解能力非常微弱。土壤降解试验表明,投加菌株AC-1可以明显促进土壤中乙草胺的降解。本研究为乙草胺的有效降解提供了数据和技术支持。展开更多
二苯并噻吩(DBT)及其衍生物微生物脱硫的4S途径需要4个酶(DszA,DszB,DszC and DszD)参与催化。其中DBT单加氧酶(DszC or DBT-MO)和DBT-砜单加氧酶(DszA or DBTO2-MO)都是黄素依赖型氧化酶,它们的催化反应需要菌体中还原型的黄素单核苷酸...二苯并噻吩(DBT)及其衍生物微生物脱硫的4S途径需要4个酶(DszA,DszB,DszC and DszD)参与催化。其中DBT单加氧酶(DszC or DBT-MO)和DBT-砜单加氧酶(DszA or DBTO2-MO)都是黄素依赖型氧化酶,它们的催化反应需要菌体中还原型的黄素单核苷酸(FMNH2),FMNH2由辅酶黄素还原酶(DszD)再生。因此,共表达DszA,DszB,DszC和DszD可以提高整个脱硫途径的速率。构建了两个不相容性表达载体pBADD和paN2并在大肠杆菌中实现了4个脱硫酶基因的共表达。DszA,DszB,DszC和DszD的可溶性蛋白表达量分别占菌体总蛋白质的7.6%,3.5%,3.1%和18%。共表达时的脱硫活性是单独用paN2表达时的5.4倍,并对工程菌休止细胞脱除模拟柴油中DBT的活性进行了研究。展开更多
基金Supported by Science and Technology Project of Guizhou Province,No.ZK[2023]380.
文摘BACKGROUND Kidney transplantation is the best option for patients with end-stage renal disease.However,the need for lifelong immunosuppression results in renal transplant recipients being susceptible to various infections.Rhodococcus equi(R.equi)is a rare opportunistic pathogen in humans,and there are limited reports of infection with R.equi in post-renal transplant recipients and no uniform standard of treat-ment.This article reports on the diagnosis and treatment of a renal transplant recipient infected with R.equi 21 mo postoperatively and summarizes the charac-teristics of infection with R.equi after renal transplantation,along with a detailed review of the literature.Here,we present the case of a 25-year-old man who was infected with R.equi 21 mo after renal transplantation.Although the clinical features at the time of presentation were not specific,chest computed tomography(CT)showed a large volume of pus in the right thoracic cavity and right middle lung atelectasis,and fiberoptic bronchoscopy showed an endobronchial mass in the right middle and lower lobe orifices.Bacterial culture and metagenomic next-generation sequen-cing sequencing of the pus were suggestive of R.equi infection.The immunosup-pressive drugs were immediately suspended and intravenous vancomycin and azithromycin were administered,along with adequate drainage of the abscess.The endobronchial mass was then resected.After the patient’s clinical symptoms and chest CT presentation resolved,he was switched to intravenous ciprofloxacin and azithromycin,followed by oral ciprofloxacin and azithromycin.The patient was re-hospitalized 2 wk after discharge for recurrence of R.equi infection.He recovered after another round of adequate abscess drainage and intravenous ciprofloxacin and azithromycin.CONCLUSION Infection with R.equi in renal transplant recipients is rare and complex,and the clinical presentation lacks specificity.Elaborate antibiotic therapy is required,and adequate abscess drainage and surgical excision are necessary.Given the recurrent nature of R.equi,patients need to be followed-up closely.
文摘为解决乙草胺残留问题,采用连续传代富集培养的方法,从长期生产乙草胺的农药厂污染土壤中分离筛选到1株乙草胺降解菌株AC-1。经过形态学特征、生理生化特征和16S rRNA基因序列系统发育分析,菌株AC-1被鉴定为红球菌属(Rhodococcus)。菌株AC-1在48h内能将0.2 m M的乙草胺完全降解,但不能矿化乙草胺。借助LC-MS,确定乙草胺降解终产物为2-氯-N-(2-乙基-6-甲基苯基)乙酰胺(CMEPA)。菌株AC-1降解乙草胺的最适温度为30℃,最适p H值为7.5。0.1 m M的Cu2+和Hg2+对菌株AC-1降解乙草胺具有很强的抑制作用,而0.1 m M的Fe2+则对菌株AC-1降解乙草胺具有微弱的促进作用。菌株AC-1对乙草胺的降解效果与起始接种量呈正相关。菌株AC-1对甲草胺和丁草胺表现出良好的降解效果,但对异丙甲草胺的降解能力非常微弱。土壤降解试验表明,投加菌株AC-1可以明显促进土壤中乙草胺的降解。本研究为乙草胺的有效降解提供了数据和技术支持。
文摘二苯并噻吩(DBT)及其衍生物微生物脱硫的4S途径需要4个酶(DszA,DszB,DszC and DszD)参与催化。其中DBT单加氧酶(DszC or DBT-MO)和DBT-砜单加氧酶(DszA or DBTO2-MO)都是黄素依赖型氧化酶,它们的催化反应需要菌体中还原型的黄素单核苷酸(FMNH2),FMNH2由辅酶黄素还原酶(DszD)再生。因此,共表达DszA,DszB,DszC和DszD可以提高整个脱硫途径的速率。构建了两个不相容性表达载体pBADD和paN2并在大肠杆菌中实现了4个脱硫酶基因的共表达。DszA,DszB,DszC和DszD的可溶性蛋白表达量分别占菌体总蛋白质的7.6%,3.5%,3.1%和18%。共表达时的脱硫活性是单独用paN2表达时的5.4倍,并对工程菌休止细胞脱除模拟柴油中DBT的活性进行了研究。
