1.Sternal Osteomyelitis Caused by Gordonia bronchialis after Open-Heart Surgery.
Jeong Hyun CHANG ; Misuk JI ; Hyo Lim HONG ; Sang Ho CHOI ; Yang Soo KIM ; Cheol Hyun CHUNG ; Heungsup SUNG ; Mi Na KIM
Infection and Chemotherapy 2014;46(2):110-114
We report the case of a deep sternal wound infection with sternal osteomyelitis caused by Gordonia bronchialis after open-heart surgery. The isolate was identified as a G. bronchialis by 16S rRNA and hsp65 gene sequencing, having initially been misidentified as a Rhodococcus by a commercial phenotypic identification system.
Osteomyelitis*
;
Rhodococcus
;
Wound Infection
3.Isolation, identification and characterization of a chloramphenicol-degrading bacterium.
Ke SHI ; Chenlei GUO ; Xiaodan MA ; Bin LIANG ; Aijie WANG
Chinese Journal of Biotechnology 2021;37(10):3653-3662
Microorganisms are the dominant players driving the degradation and transformation of chloramphenicol (CAP) in the environment. However, little bacterial strains are able to efficiently degrade and mineralize CAP, and the CAP degrading pathways mediated by oxidative reactions remain unclear. In this study, a highly efficient CAP-degrading microbial consortium, which mainly consists of Rhodococcus (relative abundance >70%), was obtained through an enrichment process using CAP-contaminated activated sludge as the inoculum. A bacterial strain CAP-2 capable of efficiently degrading CAP was isolated from the consortium and identified as Rhodococcus sp. by 16S rRNA gene analysis. Strain CAP-2 can efficiently degrade CAP under different nutrient conditions. Based on the biotransformation characteristics of the detected metabolite p-nitrobenzoic acid and the reported metabolites p-nitrobenzaldehyde and protocatechuate by strain CAP-2, a new oxidative pathway for the degradation of CAP was proposed. The side chain of CAP was oxidized and broken to generate p-nitrobenzaldehyde, which was further oxidized to p-nitrobenzoic acid. Strain CAP-2 can be used to further study the molecular mechanism of CAP catabolism, and has the potential to be used in in situ bioremediation of CAP-contaminated environment.
Biodegradation, Environmental
;
Chloramphenicol
;
RNA, Ribosomal, 16S/genetics*
;
Rhodococcus/genetics*
;
Sewage
4.Pathologic characteristics for the Rhodococcus equi infection in foals in Jeju
Kyung Ok SONG ; Hyoung Seok YANG ; Won Geun SON ; Jae Hoon KIM
Korean Journal of Veterinary Research 2019;59(3):141-149
From 1996 to 2014, 14 foals from nine farms in Jeju were diagnosed with a Rhodococcus equi infection. Clinically, most foals showed characteristic respiratory signs, including hyperthermia and dyspnea. The seasonal occurrence of R. equi infection in foals was higher in summer, such as June (eight foals; 57.1%) and July (four foals; 28.6%), than in the other seasons. The major cases of R. equi infections were observed among two-month-old (eight foals; 57.1%) and three-month-old (three foals; 21.4%) foals. Histopathologically, bronchopneumonia, abscess, and granulomatous pneumonia were the most prevalent lesions in the lungs of foals. Colonic ulcers and submucosal abscesses were found in a foal. Some foals showed granulomatous lymphadenitis and abscesses in the mesenteric and other lymph nodes. According to the polymerase chain reaction using 10 tissue samples of foals and nine R. equi isolates, the vapA gene was detected in 11/11 (100%) foals. Immunohistochemical staining using the anti-VapA monoclonal antibody was applied to detect the R. equi VapA antigen in the organs of foals. R. equi VapA antigens were demonstrated in most lungs and some mesenteric and hilar lymph nodes of 13 foals. Isolated virulent R. equi VapA bacteria showed high sensitivity to gentamicin, quinolones, rifampin, and vancomycin.
Abscess
;
Agriculture
;
Bacteria
;
Bronchopneumonia
;
Colon
;
Dyspnea
;
Fever
;
Gentamicins
;
Immunohistochemistry
;
Lung
;
Lymph Nodes
;
Lymphadenitis
;
Pneumonia
;
Polymerase Chain Reaction
;
Quinolones
;
Rhodococcus equi
;
Rhodococcus
;
Rifampin
;
Seasons
;
Ulcer
;
Vancomycin
5.A Case Report of Tsukamurella pulmonis Infection Misidentified as Atypical Mycobacteria.
Ah Ra CHO ; Hye Ryoun KIM ; Mi Kyung LEE ; Seong Ho CHOI ; Sin Weon YUN
Korean Journal of Clinical Microbiology 2010;13(2):93-97
We report a case of catheter-related bacteremia due to Tsukamurella pulmonis. T. pulmonis is a rare cause of opportunistic infection in immunosuppressed patients and in cases of indwelling foreign materials. This infection was nearly impossible to identify using conventional phenotyping methods because of its similarities to the related genera Nocardia, Rhodococcus, Gordonia, Streptomyces, Corynebacterium, and Mycobacterium. This organism was initially misidentified as Mycobacterium aubagnense through PCR-RFLP analysis. We correctly identified this organism using 16S rRNA sequencing combined with phenotyping tests.
Bacteremia
;
Catheters
;
Corynebacterium
;
Humans
;
Korea
;
Mycobacterium
;
Nocardia
;
Nontuberculous Mycobacteria
;
Opportunistic Infections
;
Rhodococcus
;
Streptomyces
6.Efficacy and safety of Nocardia rubra cell wall skeleton for the treatment of erosive oral lichen planus.
Zheng Da ZHU ; Yan GAO ; Wen Xiu HE ; Xin FANG ; Yang LIU ; Pan WEI ; Zhi Min YAN ; Hong HUA
Journal of Peking University(Health Sciences) 2021;53(5):964-969
OBJECTIVE:
To observe the efficacy and safety of Nocardia rubra cell wall skeleton (Nr-CWS) for the treatment of erosive oral lichen planus (EOLP).
METHODS:
Sixty patients with clinically and pathologically diagnosed EOLP were randomly divided into the experimental group and control group according to the random number. Patients in the experimental group were treated with lyophilized powder containing Nr-CWS combined with normal saline. Patients in the control group received topical placebo without Nr-CWS combined with normal saline. Changes in the EOLP lesion area and the patient's pain level were recorded at the timepoints of weeks 1, 2, and 4 after the two different treatments, respectively. The changes of the patient's REU scoring system (reticulation, erythema, ulceration), the visual analogue scale and the oral health impact score (OHIP-14) were compared between the experimental group and control group after treatment, and the safety indicators of the two groups at the initial diagnosis and after 4 weeks' treatment were also observed, respectively.
RESULTS:
Totally, 62 patients with clinically and pathologically diagnosed EOLP were enrolled, 2 of whom were lost to the follow-up, with 31 in the experimental group, and 29 in the control group. The mean age of the experimental group and control group were (52.9±12.4) years and (54.07±12.40) years, respectively. There was no significant difference in the oral periodontal index between the experimental group and control group. In the experimental group, the erosive area of oral lichen planus was significantly reduced 1, 2, and 4 weeks after the Nr-CWS's treatment (P < 0.05), the reduction rate was 81.75%, the patient's pain index was also decreased (P < 0.05), and in addition, the OHIP-14 was reduced (P < 0.05). The changes of the REU scoring system, the visual analogue scale and the OHIP-14 were significantly different between the experimental group and control group after treatment. There was no significant difference in the safety index between the two groups.
CONCLUSION
The priliminary data show that the Nr-CWS is effective and safe to treat EOLP.
Adult
;
Aged
;
Cell Wall Skeleton
;
Humans
;
Lichen Planus, Oral/drug therapy*
;
Middle Aged
;
Pain Measurement
;
Rhodococcus
7.Study on production of acrylamide by microbial method (II)--enzyme catalytic kinetics and de-active dynamics of nitrile hydratase.
Zhi CHEN ; Xu-Dong SUN ; Yue SHI ; Zhong-Yao SHEN ; Jian-Xun ZHAO ; Xiao-Ying SUN
Chinese Journal of Biotechnology 2002;18(2):225-230
The hydration reaction by microbial method is the crisis of the procedure of acrylamide production from acrylonitrile. This research studied the enzyme catalytic kinetics and de-active kinetics of nitrile hydratase in the type of free cell. Firstly, the effects of the concentration of cells, the temperature, pH value, the concentration of acrylonitrile and the concentration of acrylamide on the activity of nitrile hydratase was investigated. The result is that the temperature and the concentration of acrylamide are the most important among these factors. The activity of the nitrile hydratase was 5659 u/mL (broth) at 28 degrees C; the counterpart was only 663 u/mL (broth) at 5 degrees C. And the activity of NHase in solution of 45% acrylamide was just about half of that in solution of 5% acrylamide. After study on the relation of temperature and the reaction speed, It was found that the activation energy of the hydration of NHase was 65.57 kJ.mol-1. This paper studied the effects of concentration of cells, temperature, pH value, concentrations of acrylonitrile and acrylamide on the deactivation of Nhase, as well as the related enzyme de-active kinetics. The result also showed that the temperature and the concentration of acrylamide are the most important among these factors. In solution of 35% acrylamide, the residual activity was about 0% of the original value after 55 h; but in solution of 10% acrylamide, after the same period of time, the residual activity was 50% of the original one. It was also found that the concentration of acrylonitrile had little effect on the stability of NHase. The coefficient of deactivation at 28 degrees C was 21.77 times of the one at 5 degrees C. Correlating the temperature and the coefficient of deactivation, the activation energy of the de-active reaction was found to be 92.28 kJ.mol-1.
Acrylamide
;
metabolism
;
Acrylonitrile
;
metabolism
;
Catalysis
;
Hydro-Lyases
;
metabolism
;
Hydrogen-Ion Concentration
;
Kinetics
;
Rhodococcus
;
enzymology
;
Temperature
8.Cutaneous Microflora from Geographically Isolated Groups of Bradysia agrestis, an Insect Vector of Diverse Plant Pathogens.
Jong Myong PARK ; Young Hyun YOU ; Jong Han PARK ; Hyeong Hwan KIM ; Sa Youl GHIM ; Chang Gi BACK
Mycobiology 2017;45(3):160-171
Larvae of Bradysia agrestis, an insect vector that transports plant pathogens, were sampled from geographically isolated regions in Korea to identify their cutaneous fungal and bacterial flora. Sampled areas were chosen within the distribution range of B. agrestis; each site was more than 91 km apart to ensure geographical segregation. We isolated 76 microbial (fungi and bacteria) strains (site 1, 29; site 2, 29; site 3, 18 strains) that were identified on the basis of morphological differences. Species identification was molecularly confirmed by determination of universal fungal internal transcribed spacer and bacterial 16S rRNA gene sequences in comparison to sequences in the EzTaxon database and the NCBI GenBank database, and their phylogenetic relationships were determined. The fungal isolates belonged to 2 phyla, 5 classes, and 7 genera; bacterial species belonged to 23 genera and 32 species. Microbial diversity differed significantly among the geographical groups with respect to Margalef's richness (3.9, 3.6, and 4.5), Menhinick's index (2.65, 2.46, and 3.30), Simpson's index (0.06, 0.12, and 0.01), and Shannon's index (2.50, 2.17, and 2.58). Although the microbial genera distribution or diversity values clearly varied among geographical groups, common genera were identified in all groups, including the fungal genus Cladosporium, and the bacterial genera Bacillus and Rhodococcus. According to classic principles of co-evolutionary relationship, these genera might have a closer association with their host insect vector B. agrestis than other genera identified. Some cutaneous bacterial genera (e.g., Pseudomonas) displaying weak interdependency with insect vectors may be hazardous to agricultural environments via mechanical transmission via B. agrestis. This study provides comprehensive information regarding the cutaneous microflora of B. agrestis, which can help in the control of such pests for crop management.
Bacillus
;
Biodiversity
;
Cladosporium
;
Databases, Nucleic Acid
;
Genes, rRNA
;
Insect Vectors*
;
Insects*
;
Korea
;
Larva
;
Plants*
;
Rhodococcus
9.Pyridine degradation characteristics of Rhodococcus sp. LV4 under high salinity conditions.
Ying WANG ; Hu CHEN ; Mengdi XU ; Yongkang LÜ
Chinese Journal of Biotechnology 2023;39(3):1202-1216
Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to Rhodococcus on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.
Rhodococcus/genetics*
;
Phylogeny
;
Extracellular Polymeric Substance Matrix/metabolism*
;
Sewage
;
Biodegradation, Environmental
;
Pyridines/metabolism*
10.Central Venous Catheter-Related Microbacterium Bacteremia Identified by 16S ribosomal RNA Gene Sequencing.
Chang Jin MOON ; Jong Hee SHIN ; Eun Sun JEONG ; Seung Jung KEE ; Soo Hyun KIM ; Myung Geun SHIN ; Soon Pal SUH ; Dong Wook RYANG
Korean Journal of Clinical Microbiology 2009;12(2):97-101
We describe here a case of central venous catheter (CVC)-related bacteremia caused by Microbacterium species in a 14-year-old patient, who had received chemotherapy for acute lymphoblastic leukemia. All nine blood cultures obtained from admission day 2 to day 62 yielded the same yellow-pigmented coryneform rod. Both Vitek 2 (bioMerieux, USA) and MicroScan (Dade Behring, USA) identified the isolate as Micrococcus species, and the API Coryne (bioMerieux, France) identified the isolate as Rhodococcus or Brevibacterium species. However, the 16S rRNA gene sequence showed a 99% identity with Microbacterium species. The bacteremia was recurrent or persistent over 60 days despite alternate systemic antibiotic therapy, but blood culture became negative after an addition of teicoplanin lock therapy for eradicating CVC-related bacteremia. This represents the first report of CVC-related Microbacterium bacteremia cured by antibiotic lock therapy in Korea.
Adolescent
;
Bacteremia
;
Brevibacterium
;
Central Venous Catheters
;
Genes, rRNA
;
Humans
;
Micrococcus
;
Precursor Cell Lymphoblastic Leukemia-Lymphoma
;
Rhodococcus
;
RNA, Ribosomal, 16S
;
Teicoplanin