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1.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 40(10): 562-567, dic. 2022. tab
Artigo em Espanhol | IBECS | ID: ibc-212841

RESUMO

Introduction: The incidence of infections caused by aerobic actinomycetes is increasing. Recent changes in taxonomy and the variability in susceptibility patterns among species make necessary a proper identification and antibiotic susceptibility testing. Material and methods: Fifty-three strains of aerobic actinomycetes were identified by MALDI-TOF MS using the VITEK MS Mycobacterium/Nocardia kit (bioMérieux, France) in a tertiary hospital in Spain during a six-year period. Antimicrobial susceptibility testing of the isolates was performed using the Sensititre Rapmycoi microdilution panel (Thermo Fisher Scientific, Massachusetts, USA). Results: Forty strains of Nocardia spp. were identified in the study, being N. farcinica and N. cyriacigeorgica the most prevalent ones. All isolates were susceptible to linezolid and the resistance to amikacin was only observed in one isolate of Gordonia sputi. Resistance to cotrimoxazole was only found in five isolates. Conclusions: Routine identification and antimicrobial susceptibility testing of aerobic actinomycetes is advisable for an efficient identification of species and effective treatment.(AU)


Introducción: La incidencia de infecciones por actinomicetos aerobios está aumentando. Los recientes cambios en la taxonomía y la variabilidad en la sensibilidad entre especies hacen necesaria una identificación y estudio de sensibilidad adecuados. Material y métodos: Se identificaron 53 cepas de actinomicetos aerobios mediante MALDI-TOF utilizando el kit VITEK-MS Mycobacterium/Nocardia (bioMérieux, Francia) en un hospital terciario español durante seis años. Los estudios de sensibilidad de los aislados se realizaron utilizando el panel de microdilución Sensititre Rapmycoi (Thermo Fisher Scientific, Massachusetts, EE. UU.). Resultados: Se identificaron 40 cepas de Nocardia spp., siendo Nocardia farcinica y Nocardia cyriacigeorgica las más prevalentes. Todos los aislados fueron sensibles a linezolid, y solo se detectó resistencia a amikacina en un aislado de Gordonia sputi. Solo se encontró resistencia al cotrimoxazol en cinco aislados. Conclusiones: Es aconsejable realizar la identificación de rutina y las pruebas de sensibilidad antimicrobiana de los actinomicetos aerobios para conseguir una identificación eficiente de las especies y un tratamiento eficaz.(AU)


Assuntos
Humanos , Masculino , Feminino , Técnicas In Vitro , Epidemiologia , Sensibilidade e Especificidade , Actinomycetales , Infecções por Actinomycetales , Nocardia , Bactéria Gordonia , Doenças Transmissíveis , Espanha
2.
FEMS Microbiol Lett ; 369(1)2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-36513328

RESUMO

The secondary metabolites produced by microorganisms are a source of novel compounds with antitumor activities. In this study, we isolated biologically active secondary metabolites produced by microorganisms in the intestinal tract of Periplaneta americana. Based on the 16S rRNA gene sequencing, Gordonia hongkongensis WA12-1-1 was identified as the main microorganisms in the intestinal tract of P. americana. The obtained sequence was deposited in the National Center for Biotechnology Information (NCBI) database under the accession number MZ348554. The isolated secondary metabolites were separated and purified by thin layer chromatography, silica gel column chromatography, Sephadex column chromatography, open octadecyl silane column chromatography, high-performance liquid chromatography (HPLC), and semipreparative HPLC. Next, the structure of individual compounds was determined by ultraviolet spectroscopy, nuclear magnetic resonance, and mass spectrometry. A total of 20 compounds were isolated from the secondary metabolites produced by G. hongkongensis WA12-1-1. A total of 12 compounds were obtained from the crude ethyl acetate extract of the culture supernatant and eight from the cellular fraction. Compound 1 was identified as a triterpenoid named gordonterpene and showed cytotoxicity against A549 and HepG2 cell lines. These findings form a basis for further studies on the bioactivity of gordonterpene to tumor cells.


Assuntos
Bactéria Gordonia , Periplaneta , Triterpenos , Animais , Triterpenos/farmacologia , RNA Ribossômico 16S , Espectroscopia de Ressonância Magnética
3.
PLoS One ; 17(11): e0276603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36395171

RESUMO

Holins are bacteriophage-encoded transmembrane proteins that function to control the timing of bacterial lysis event, assist with the destabilization of the membrane proton motive force and in some models, generate large "pores" in the cell membrane to allow the exit of the phage-encoded endolysin so they can access the peptidoglycan components of the cell wall. The lysis mechanism has been rigorously evaluated through biochemical and genetic studies in very few phages, and the results indicate that phages utilize endolysins, holins and accessory proteins to the outer membrane to achieve cell lysis through several distinct operational models. This observation suggests the possibility that phages may evolve novel variations of how the lysis proteins functionally interact in an effort to improve fitness or evade host defenses. To begin to address this hypothesis, the current study utilized a comprehensive bioinformatic approach to systematically identify the proteins encoded by the genes within the lysis cassettes in 16 genetically diverse phages that infect the Gram-positive Gordonia rubripertincta NRLL B-16540 strain. The results show that there is a high level of diversity of the various lysis genes and 16 different genome organizations of the putative lysis cassette, many which have never been described. Thirty-four different genes encoding holin-like proteins were identified as well as a potential holin-major capsid fusion protein. The holin-like proteins contained between 1-4 transmembrane helices, were not shared to a high degree amongst the different phages and are present in the lysis cassette in a wide range of combinations of up to 4 genes in which none are duplicated. Detailed evaluation of the transmembrane domains and predicted membrane topologies of the holin-like proteins show that many have novel structures that have not been previously characterized. These results provide compelling support that there are novel operational lysis models yet to be discovered.


Assuntos
Bacteriófagos , Bactéria Gordonia , Bacteriófagos/genética , Bacteriófagos/metabolismo , Bacteriólise , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Biologia Computacional , Proteínas Virais/genética , Proteínas Virais/metabolismo , Bactéria Gordonia/metabolismo
4.
Int J Syst Evol Microbiol ; 72(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36256446

RESUMO

The taxonomic status of two Gordonia strains, designated BEN371 and CON9T, isolated from stable foams on activated sludge plants was the subject of a polyphasic study which also included the type strains of Gordonia species and three authenticated Gordonia amarae strains recovered from such foams. Phylogenetic analyses of 16S rRNA gene sequences showed that these isolates formed a compact cluster suggesting a well-supported lineage together with a second branch containing the G. amarae strains. A phylogenomic tree based on sequences of 92 core genes extracted from whole genome sequences of the isolates, the G. amarae strains and Gordonia type strains confirmed the assignment of the isolates and the G. amarae strains to separate but closely associated lineages. Average nucleotide index (ANI) and digital DNA-DNA hybridisation (dDDH) similarities showed that BEN371 and CON9T belonged to the same species and had chemotaxonomic and morphological features consistent with their assignment to the genus Gordonia. The isolates and the G. amarae strains were distinguished using a range of phenotypic features and by low ANI and dDDH values of 84.2 and 27.0 %, respectively. These data supplemented with associated genome characteristics show that BEN371 and CON9T represent a novel species of the genus Gordonia. The name proposed for members of this taxon is Gordonia pseudamarae sp. nov. with isolate CON9T (=DSM 43602T=JCM 35249T) as the type strain.


Assuntos
Actinobacteria , Bactéria Gordonia , Purificação da Água , Esgotos/microbiologia , RNA Ribossômico 16S/genética , Filogenia , DNA Bacteriano/genética , Composição de Bases , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Ácidos Graxos/química , Nucleotídeos
6.
Viruses ; 14(8)2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-36016269

RESUMO

Bacteriophages infecting bacteria of the genus Gordonia have increasingly gained interest in the scientific community for their diverse applications in agriculture, biotechnology, and medicine, ranging from biocontrol agents in wastewater management to the treatment of opportunistic pathogens in pulmonary disease patients. However, due to the time and costs associated with experimental isolation and cultivation, host ranges for many bacteriophages remain poorly characterized, hindering a more efficient usage of bacteriophages in these areas. Here, we perform a series of computational genomic inferences to predict the putative host ranges of all Gordonia cluster DR bacteriophages known to date. Our analyses suggest that BiggityBass (as well as several of its close relatives) is likely able to infect host bacteria from a wide range of genera-from Gordonia to Nocardia to Rhodococcus, making it a suitable candidate for future phage therapy and wastewater treatment strategies.


Assuntos
Bacteriófagos , Bactéria Gordonia , Bacteriófagos/genética , Genoma Viral , Genômica , Bactéria Gordonia/genética , Humanos , Filogenia
7.
Enferm Infecc Microbiol Clin (Engl Ed) ; 40(5): 255-257, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35577444

RESUMO

PURPOSE: Gordonia species are known to be opportunistic human pathogens causing secondary infections. We present the second case in the world of endocarditis caused by Gordonia bronchialis and a review of all the cases of endocarditis caused by Gordonia spp. METHODS: The identification was performed by matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing were performed to confirm the identification. Antimicrobial susceptibility was performed by MIC test Strip on Mueller-Hinton agar supplemented with 5% defibrinated sheep blood according to Clinical and Laboratory Standards Institute. RESULTS: Pacemaker-induced endocarditis due to Gordonia bronchialis infection was determined in an 88-year old woman. The patient was treated with ceftriaxone and ciprofloxacin until completing 6 weeks from the pacemaker explant with a good evolution. CONCLUSION: The case presented supports the pathogenic role of Gordonia bronchialis as an opportunistic pathogen and highlights the high risk of suffering infections caused by environmental bacteria.


Assuntos
Endocardite , Bactéria Gordonia , Marca-Passo Artificial , Actinobacteria , Animais , Bactéria Gordonia/genética , Humanos , Marca-Passo Artificial/efeitos adversos , RNA Ribossômico 16S/genética , Ovinos/genética
8.
Artigo em Inglês | IBECS | ID: ibc-203500

RESUMO

PurposeGordonia species are known to be opportunistic human pathogens causing secondary infections. We present the second case in the world of endocarditis caused by Gordonia bronchialis and a review of all the cases of endocarditis caused by Gordonia spp.MethodsThe identification was performed by matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing were performed to confirm the identification. Antimicrobial susceptibility was performed by MIC test Strip on Mueller-Hinton agar supplemented with 5% defibrinated sheep blood according to Clinical and Laboratory Standards Institute.ResultsPacemaker-induced endocarditis due to Gordonia bronchialis infection was determined in an 88-year old woman. The patient was treated with ceftriaxone and ciprofloxacin until completing 6 weeks from the pacemaker explant with a good evolution.ConclusionThe case presented supports the pathogenic role of Gordonia bronchialis as an opportunistic pathogen and highlights the high risk of suffering infections caused by environmental bacteria.


ObjetivoLas especies de Gordonia son patógenos humanos oportunistas que causan infecciones secundarias. Presentamos el segundo caso en el mundo de endocarditis causada por Gordonia bronchialis, así como una revisión de todos los casos de endocarditis causados por Gordonia spp.MétodosLa identificación fue realizada mediante espectrometría de masas MALDI-TOF MS, y se confirmó mediante secuenciación del gen 16S rRNA. La susceptibilidad antimicrobiana se realizó mediante tiras reactivas MIC en agar Müller-Hinton suplementado con un 5% de sangre ovina desfibrinada, conforme al Clinical and Laboratory Standards Institute (CLSI).ResultadosLa endocarditis del marcapasos debido a infección por Gordonia bronchialis se encontró en una mujer de 88 años. La paciente fue tratada con ceftriaxona y ciprofloxacina hasta completar el periodo de 6 semanas desde el explante del marcapasos, con buena evolución.ConclusiónEste caso respalda el rol patogénico de Gordonia bronchialis como patógeno oportunista, subrayando el alto riesgo de padecer infecciones causadas por bacterias ambientales.


Assuntos
Humanos , Feminino , Idoso , Ciências da Saúde , Endocardite , Marca-Passo Artificial , Bactéria Gordonia , Assistência Centrada no Paciente , Doenças Transmissíveis , Microbiologia , Estudos de Casos e Controles , Ceftriaxona , Ciprofloxacina
9.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 49(2): 1-5, Abril - Junio, 2022. ilus
Artigo em Espanhol | IBECS | ID: ibc-203192

RESUMO

La mastitis granulomatosa idiopática es una entidad rara, benigna y crónica de causa desconocida que afecta a la mama. Es un diagnóstico de exclusión. Se deben descartar, entre otras etiologías, la tuberculosis, las infecciones, la sarcoidosis y otras enfermedades autoinmunes, como la arteritis de células gigantes. Los principales retos que plantea esta entidad son su diagnóstico diferencial con enfermedad maligna y su tratamiento. La afectación mamaria es anecdótica y ha sido solo reportada en relación con prótesis mamarias. Presentamos el caso de una paciente diagnosticada de mastitis granulomatosa idiopática complicada con un absceso de mama por Gordonia sputi.


Idiopathic granulomatous mastitis is a rare, benign, chronic entity of unknown cause affecting the breast. It is a diagnosis of exclusion. Among other aetiologies, tuberculosis, infections, sarcoidosis, and other autoimmune diseases such as giant cell arteritis must be ruled out. The main challenges posed by this entity are its differential diagnosis with malignant pathology and its treatment.Gordonia spp. are a group of emerging pathogens that are mainly associated with infections associated with medical devices, mainly catheters. Breast involvement is anecdotal and has only been reported in relation to breast prostheses.We present the case of a patient diagnosed with idiopathic granulomatous mastitis complicated with a breast abscess due to Gordonia sputi.


Assuntos
Feminino , Adulto , Ciências da Saúde , Mastite Granulomatosa , Bactéria Gordonia , Abscesso , Mama
11.
Curr Microbiol ; 79(3): 82, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35107610

RESUMO

Although conventional oil refining process like hydrodesulfurization (HDS) is capable of removing sulfur compounds present in crude oil, it cannot desulfurize recalcitrant organosulfur compounds such as dibenzothiophenes (DBTs), benzothiophenes (BTs), etc. Biodesulfurization (BDS) is a process of selective removal of sulfur moieties from DBT or BT by desulfurizing microbes. Therefore, BDS can be used as a complementary and economically feasible technology to achieve deep desulfurization of crude oil without affecting the calorific value. In the recent past, members of biodesulfurizing actinomycete genus Gordonia, isolated from versatile environments like soil, activated sludge, human beings etc. have been greatly exploited in the field of petroleum refining technology. The bacterium Gordonia sp. is slightly acid-fast and has been used for unconventional but potential oil refining processes like BDS in petroleum refineries. Gordonia sp. is unique in a way, that it can desulfurize both aliphatic and aromatic organosulfurs without affecting the calorific value of hydrocarbon molecules. Till date, approximately six different species and nineteen strains of the genus Gordonia have been recognized for BDS activity. Various factors such as enzyme specificity, availability of essential cofactors, feedback inhibition, toxicity of organic pollutants and the oil-water separations limit the desulfurization rate of microbial biocatalyst and influence its commercial applications. The current review selectively highlights the role of this versatile genus in removing sulfur from fossil fuels, mechanisms and future prospects on sustainable environment friendly technologies for crude oil refining.


Assuntos
Bactéria Gordonia , Petróleo , Combustíveis Fósseis , Bactéria Gordonia/genética , Humanos , Enxofre , Compostos de Enxofre
12.
Environ Technol ; 43(17): 2604-2611, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33577396

RESUMO

A previous isolated Gordonia sp. (Lff) was used to degrade di-n-octyl phthalate (DOP) contamination in both aqueous solution and soil. The influence of temperature, pH, inoculum size, salt content and initial concentration of DOP on DOP degradation by Lff were analysed. The response of soil bacterial community to DOP and Lff was also analysed by Illumina MiSeq sequence method. Results showed that the optimal temperature, pH, inoculum size and salt content were 35oC, 8.0, 5% and <5%, respectively. Under the optimal condition, more than 91.25% of DOP with different initial concentrations (100-2000 mg/L) could be degraded by Lff. Kinetics analysis indicated that biodegradation of DOP by Lff could be described by first-order kinetics (R2 > 0.917) with the half-life (t1/2) changing irregularly between 0.58 and 0.83 d. In addition, Lff enhanced the removal of DOP in soil and alleviated the toxicity of DOP on soil microorganisms. Furthermore, its influence on soil bacterial community is not obvious. These results suggested that Lff was effective in remediating DOP contamination in different environments.


Assuntos
Bactéria Gordonia , Ácidos Ftálicos , Biodegradação Ambiental , Bactéria Gordonia/metabolismo , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Solo
13.
J Hazard Mater ; 422: 126900, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34418829

RESUMO

Carbon sources have been reported to determine the bio-demulsifying performance and mechanisms. However, the genetic regulation of carbon sources-mediated bio-demulsification remains unclear. Here, the effects of ß-oxidation, stress response, and nitrate metabolism on the demulsification of alkaline-surfactant-polymer flooding produced water by Gordonia sp. TD-4 were investigated. The results showed that competitive adsorption-derived demulsification was mediated by oil-soluble carbon sources (paraffin). Surface-active lipopeptides responsible for competitive adsorption-derived demulsification could be biosynthesized by the nonribosomal peptide synthetases and polyketide synthases using oil-soluble carbon sources. Bio-flocculation-derived demulsification was mediated by water-soluble carbon sources. Water-soluble carbon sources (sodium acetate and glucose) mediated the process of the dissimilatory reduction of nitrate to ammonia, which resulted in the variable accumulation of nitrite. The accumulated nitrite (>180 mg-N/L) stimulated stress response and induced the upregulation of chaperone-associated genes. The upregulation of chaperonins increased the cell surface hydrophobicity and the cation-dependent bio-flocculating performance, which were responsible for bio-flocculation-derived demulsification. The ß-oxidation of fatty acids significantly affected both competitive adsorption-derived demulsification and bio-flocculation-derived demulsification. This study illustrates the synergistic effects of nitrogen sources and carbon sources on the regulation of bio-demulsifying mechanisms of TD-4 and identifies two key functional gene modules responsible for the regulation of bio-demulsifying mechanisms.


Assuntos
Proteínas de Bactérias/metabolismo , Bactéria Gordonia/enzimologia , Proteínas de Choque Térmico/metabolismo , Nitratos , Peptídeo Sintases/metabolismo , Policetídeo Sintases/metabolismo , Carbono , Emulsões
15.
Genomics ; 113(6): 4327-4336, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34801686

RESUMO

Gordonia are Gram-positive bacteria which have immense biotechnological potential. Genomes of several Gordonia spp. have been sequenced but a detailed analysis of the differentially expressed genes during growth, the promoters which drive their expression and the information on the core promoter sequence is lacking. Here, we report the identification of core promoter sequence in Gordonia sp. IITR100. The GC content of the promoters was found to be within a range of 62-65%. The 5'-UTR length in the genes was also analysed and about 56% promoters were found to have long 5'-UTR. The functionality of the promoters was validated by microarray profiling. Based on the differential expression of genes, two growth phase dependent promoters PdsbA and Pglx were isolated and analysed. They add to the existing repertoire of the promoters functional in both Gram-negative and Gram-positive bacteria. Our results suggest that the core promoter sequence identified is conserved in members of Gordonia spp. and is similar to that of other members of Actinobacteria.


Assuntos
Actinobacteria , Bactéria Gordonia , Actinobacteria/genética , Composição de Bases , Bactéria Gordonia/genética , Regiões Promotoras Genéticas
16.
Artigo em Inglês | MEDLINE | ID: mdl-34280084

RESUMO

Four mesophilic and Gram-stain-positive strains (zg-686T/zg-691 and HY186T/HY189) isolated from Tibetan Plateau wildlife (PR China) belong to the genus Gordonia according to 16S rRNA gene and genomic sequence-based phylogenetic/genomic results. They have a DNA G+C content range of 67.4-68.3 mol% and low DNA relatedness (19.2-27.6 %) with all available genomes in the genus Gordonia. Strains zg-686T/zg-691 and HY186T/HY189 had C18 : 1ω9c, C18 : 0 10-methyl, C16 : 1 ω7c/C16 : 1ω6c and C16 : 0 as major cellular fatty acids. The polar lipids detected in strains zg-686T and HY186T included diphosphatidylglycerol, phosphatidylethanolamine, phosphatidyl inositol mannoside and phosphatidylinositol. The respiratory quinones comprised MK8(H2) (10.8 %) and MK9(H2) (89.2 %) for strain zg-686T, and MK6 (7.7 %), MK8(H2) (8.4 %), MK8(H4) (3.1 %) and MK9(H2) (80.8 %) for strain HY186T. Optimal growth conditions were pH 7.0, 35-37 °C and 0.5-1.5 % NaCl (w/v) for strains pair zg-686T/zg-691, and pH 7.0, 28 °C and 1.5 % (w/v) NaCl for strains pair HY186T/HY189. Based on these genotypic and phenotypic results, these four strains could be classified as two different novel species in the genus Gordonia, for which the names Gordonia jinghuaiqii sp. nov. and Gordonia zhaorongruii sp. nov. are proposed. The type strains are zg-686T (=GDMCC 1.1715T =JCM 33890T) and HY186T (=CGMCC 4.7607T =JCM 33466T), respectively.


Assuntos
Animais Selvagens/microbiologia , Bactéria Gordonia/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Bactéria Gordonia/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/química
17.
Biodegradation ; 32(2): 113-125, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33677743

RESUMO

The enzymatic degradation of the rubber polymer poly(cis-1,4-isoprene), e.g. by the latex clearing protein Lcp1VH2 of Gordonia polyisoprenivorans VH2 has been demonstrated with latex milk or pure isoprene-rubber particles, recently. Unfortunately, carbon black filled vulcanized rubber (CFVR) making the biggest part of worldwide rubber wastes, contains several harmful additives making microbial and enzymatic rubber degradation challenging. However, this study demonstrates the successful enzymatic cleavage of industrially produced CFVR. The formation of the cleavage products, oligo(cis-1,4-isoprenoids), from incubating CFVR particles with Lcp1VH2 was detected by HPLC-MS. Various organic solvents were tested to remove harmful or inhibiting additives like antioxidants to enhance product formation. The pretreatment of CFVR particles, especially with chloroform or cyclohexane, significantly improved the degradation. It was also demonstrated that reducing the particles size and thus increasing the enzymatically accessible surface area of the particles led to a strong acceleration of the degradation process. Furthermore, ATR-IR analyses showed that Lcp1VH2 led to the functionalization of the rubber particle surface with carbonyl groups by cleaving isoprene chains, still linked to the particle. Both, the oligo(cis-1,4-isoprenoids) as well as the functionalized rubber particles, are potentially important products, which can be reused as fine chemicals or as additives in rubber production. The present study, showing the enzymatic degradation of common CFVR for the first time, takes an important step towards a new way of rubber waste disposal and indicates the economic feasibility of an efficient and environmentally friendly recycling process by using the rubber oxygenase Lcp1VH2.


Assuntos
Actinobacteria , Bactéria Gordonia , Biodegradação Ambiental , Látex
18.
Microbiology (Reading) ; 166(12): 1181-1190, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33215983

RESUMO

WhiB is a transcription regulator which has been reported to be involved in the regulation of cell morphogenesis, cell division, antibiotic resistance, stress, etc., in several members of the family Actinomycetes. The present study describes functional characterization of a WhiB family protein, WhiB1 (protein ID: WP_065632651.1), from Gordonia sp. IITR100. We demonstrate that WhiB1 affects chromosome segregation and cell morphology in recombinant Escherichia coli, Gordonia sp. IITR100 as well as in Rhodococcus erythropolis. Multiple sequence alignment suggests that WhiB1 is a conserved protein among members of the family Actinomycetes. It has been reported that overexpression of WhiB1 leads to repression of the biodesulfurization operon in recombinant E. coli, Gordonia sp. IITR100 and R. erythropolis. A WhiB1-mut containing a point mutation Q116A in the DNA binding domain of WhiB1 led to partial alleviation of repression of the biodesulfurization operon. We show for the first time that the WhiB family protein WhiB1 is also involved in repression of the biodesulfurization operon by directly binding to the dsz promoter DNA.


Assuntos
Proteínas de Bactérias/metabolismo , Bactéria Gordonia/metabolismo , Fatores de Transcrição/metabolismo , Actinobacteria/química , Actinobacteria/classificação , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Segregação de Cromossomos , Sequência Conservada , Regulação Bacteriana da Expressão Gênica , Bactéria Gordonia/química , Bactéria Gordonia/citologia , Bactéria Gordonia/crescimento & desenvolvimento , Mutação , Óperon , Oxigenases/genética , Regiões Promotoras Genéticas , Fatores de Transcrição/química , Fatores de Transcrição/genética
19.
Int J Syst Evol Microbiol ; 70(8): 4537-4543, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32667871

RESUMO

A novel actinobacterium, designated strain HNM0687T, was isolated from mangrove soil samples collected from Hainan Province, PR China and its polyphasic taxonomy was studied. Based on the results of 16S rRNA gene sequence analysis, strain HNM0687T was closely related to Gordonia bronchialis NBRC 16047T (98.7 %), Gordonia rhizosphera NBRC 16068T (98.2 %), Gordonia oryzae RS15-1ST (97.9 %), Gordonia polyisoprenivorans NBRC 16320T (97.7 %) and Gordonia sediminis AMA 120T (97.7 %). Genome-based comparisons revealed a clear distinction in average nucleotide identity values between strain HNM0687T and its closely related strains (74.4-78.3 %). Strain HNM0687T contained meso-diaminopimelic acid, arabinose and galactose in whole-cell hydrolysates. Mycolic acid was present. The menaquinones of strain HNM0687T were MK-9(H2) and MK-7(H2). The phospholipids of the isolate were composed of diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The major fatty acids were C16 : 0, C16 : 1 ω7c/C16 : 1 ω6c, C18 : 010-methyl (TBSA), C18 : 0 and C18 : 1 ω9c. Based on its genotypic, chemotaxonomic and phenotypic characteristics, it is concluded that strain HNM0687T represents a novel species of the genus Gordonia for which the name Gordonia mangrovi sp. nov. is proposed. The type strain is HNM0687T (=CCTCC AA 2019074 T=KCTC 49383 T).


Assuntos
Bactéria Gordonia/classificação , Filogenia , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Bactéria Gordonia/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/química
20.
J Environ Manage ; 270: 110825, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32501236

RESUMO

Nowadays, the production of green transportation fuels is essential for a healthy life and environment. Effective and complete removal of organosulfur recalcitrant compounds from fuel oils is crucial to meet the stringent requirements of sulfur standards. However, the industry's solution (Hydrodesulfurization, HDS) is not effective in the removal of complex sulfur heterocyclic hydrocarbons. Thus, the development of more efficient and ecofriendly/sustainable desulfurization methods is critical, as either an alternative or a complement to HDS, foreseeing the production of ultra-low sulfur fuels (ULSF). Among the desulfurization techniques available, microbial desulfurization of organosulfur hydrocarbons (biodesulfurization, BDS) is attracting great attention. BDS is carried out at mild operation conditions, making it energetically cheaper and more ecofriendly, since it does not require hydrogen and produces far less greenhouse gases emission than HDS. In this context, the behavior of Gordonia alkanivorans strain 1B, a desulfurizing bacterium and hyper-pigment producer, was evaluated in the presence of four sulfur sources common in fuel oils: dibenzothiophene (DBT); 4-mDBT; 4,6-dmDBT and 4,6-deDBT (single/mixed), in terms of both desulfurization rate and overall carotenoid production. Simultaneously, the influence of the carbon source used (fructose vs glucose) on the overall effectiveness of the coupled bioprocesses was also assessed. The results obtained highlight the potential of strain 1B to desulfurize all the tested recalcitrant compounds and simultaneously produce carotenoids. However, the highest BDS values were observed for 4,6-deDBT (5.75 µmol/g (DCW)/h) and for the mix of DBTs (5.20 µmol/g (DCW)/h), when fructose was used as carbon source. Indeed, when the mixture of DBTs ("model oil surrogate") was desulfurized by cells growing in fructose both desulfurization rate and total pigments amount were higher than those observed for glucose growing cells. Moreover, under these conditions, the strain 1B was able to produce high added-value carotenoids, namely astaxanthin, lutein and canthaxanthin. Hence, these results are promising when aiming to achieve a scale-up scenario. In fact, the inclusion of the production of high added-value products within a BDS process targeting ULSF may be a sustainable way to turn its scale-up economically viable.


Assuntos
Bactéria Gordonia , Tiofenos , Actinobacteria , Biodegradação Ambiental , Carotenoides
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