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1.
PLoS One ; 13(4): e0195299, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29630677

RESUMO

Old Yellow Enzymes (OYEs) are NAD(P)H dehydrogenases of not fully resolved physiological roles that are widespread among bacteria, plants, and fungi and have a great potential for biotechnological applications. We determined the apo form crystal structure of a member of the OYE class, glycerol trinitrate reductase XdpB, from Agrobacterium bohemicum R89-1 at 2.1 Å resolution. In agreement with the structures of the related bacterial OYEs, the structure revealed the TIM barrel fold with an N-terminal ß-hairpin lid, but surprisingly, the structure did not contain its cofactor FMN. Its putative binding site was occupied by a pentapeptide TTSDN from the C-terminus of a symmetry related molecule. Biochemical experiments confirmed a specific concentration-dependent oligomerization and a low FMN content. The blocking of the FMN binding site can exist in vivo and regulates enzyme activity. Our bioinformatic analysis indicated that a similar self-inhibition could be expected in more OYEs which we designated as subgroup OYE C1. This subgroup is widespread among G-bacteria and can be recognized by the conserved sequence GxxDYP in proximity of the C termini. In proteobacteria, the C1 subgroup OYEs are typically coded in one operon with short-chain dehydrogenase. This operon is controlled by the tetR-like transcriptional regulator. OYEs coded in these operons are unlikely to be involved in the oxidative stress response as the other known members of the OYE family because no upregulation of XdpB was observed after exposing A. bohemicum R89-1 to oxidative stress.


Assuntos
Agrobacterium/enzimologia , Proteínas de Bactérias/química , NADPH Desidrogenase/química , Oxirredutases/química , Agrobacterium/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Biologia Computacional , Cristalografia por Raios X , Mononucleotídeo de Flavina/metabolismo , Genes Bacterianos , Cinética , Modelos Moleculares , NADPH Desidrogenase/genética , NADPH Desidrogenase/metabolismo , Óperon , Estresse Oxidativo , Oxirredutases/genética , Oxirredutases/metabolismo , Estrutura Quaternária de Proteína
2.
Syst Appl Microbiol ; 41(3): 184-190, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29402492

RESUMO

Two non-pathogenic strains R89-1 and R90T isolated from poppy seed (Papaver somniferum L.) wastes were phenotypically and genotypically characterized. Multilocus sequence analysis (MLSA) was conducted with six genes (atpD, glnA, gyrB, recA, rpoB, 16S rRNA). The strains represented a new species which clustered with Agrobacterium rubi NBRC 13261T and Agrobacterium skierniewicense Ch11T type strains. MLSA was further accompanied by whole-genome phylogeny, in silico DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses for both strains. ANI and dDDH values were deep below the species delineation threshold. Phenotypic features of the novel strains unequivocally allowed their differentiation from all other Agrobacterium species. Unlike other agrobacteria, the strains were salt sensitive and were able to biotransform morphine alkaloids. The dominant cellular fatty acids are 18:1 w7c, 16:0 and 12:0 aldehyde/16:1 iso I/14:0 3OH summed in feature 2 and the major respiratory quinine is Q-10 (87%). The DNA G+C content is 56mol%. Microbial community analysis indicated probable association with P. somniferum plant material. Altogether, these characteristics showed that strains R90T and R89-1 represent a new species of the genus Agrobacterium which we propose to name Agrobacterium bohemicum. The type strain of A. bohemicum is R90T (=CCM 8736T=DSM 104667T).


Assuntos
Agrobacterium/classificação , Papaver/microbiologia , Filogenia , Sementes/microbiologia , Agrobacterium/genética , Agrobacterium/isolamento & purificação , Composição de Bases , Biotransformação , República Tcheca , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
3.
Folia Microbiol (Praha) ; 63(3): 273-282, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29127620

RESUMO

The bacterial strain KDF8 capable of growth in the presence of diclofenac and codeine analgesics was obtained after chemical mutagenesis of nature isolates from polluted soils. The strain KDF8 was identified as Raoultella sp. based on its morphology, biochemical properties, and 16S rRNA gene sequence. It was deposited in the Czech Collection of Microorganisms under the number CCM 8678. A growing culture efficiently removed diclofenac (92% removal) and partially also codeine (about 30% degradation) from culture supernatants within 72 h at 28 °C. The degradation of six analgesics by the whole cell catalyst was investigated in detail. The maximum degradation of diclofenac (91%) by the catalyst was achieved at pHINI of 7 (1 g/L diclofenac). The specific removal rate at high concentrations of diclofenac and codeine increased up to 16.5 mg/gCDW per h and 5.1 mg/gCDW per h, respectively. HPLC analysis identified 4'-hydroxydiclofenac as a major metabolite of diclofenac transformation and 14-hydroxycodeinone as codeine transformation product. The analgesics ibuprofen and ketoprofen were also removed, albeit to a lower extent of 3.2 and 2.0 mg/gCDW per h, respectively. Naproxen and mefenamic acid were not degraded.


Assuntos
Analgésicos/metabolismo , Enterobacteriaceae/metabolismo , Poluentes Químicos da Água/metabolismo , Analgésicos/toxicidade , Codeína/metabolismo , Codeína/toxicidade , DNA Bacteriano/genética , Diclofenaco/metabolismo , Diclofenaco/toxicidade , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do Solo , Temperatura
4.
Genome Announc ; 5(38)2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28935728

RESUMO

Strain Pantoea agglomerans JM1 was isolated from the soil of a microbiome that had been exposed to polluting pharmaceuticals. The bacterium exhibited enzymatic activities useful for the biotransformation of beta-lactams. The genome of the strain was assembled and described, and the gene encoding valacyclovir-like hydrolase was identified.

5.
Folia Microbiol (Praha) ; 62(5): 417-424, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28281229

RESUMO

This study deals with the potential of Pichia pastoris X-33 for the production of penicillin G acylase (PGAA) from Achromobacter sp. CCM 4824. Synthetic gene matching the codon usage of P. pastoris was designed for intracellular and secretion-based production strategies and cloned into vectors pPICZ and pPICZα under the control of AOX1 promoter. The simple method was developed to screen Pichia transformants with the intracellularly produced enzyme. The positive correlation between acylase production and pga gene dosage for both expression systems was demonstrated in small scale experiments. In fed-batch bioreactor cultures of X-33/PENS2, an extracellular expression system, total PGAA expressed from five copies reached 14,880 U/L of an active enzyme after 142 h; however, 60% of this amount retained in the cytosol. The maximum PGAA production of 31,000 U/L was achieved intracellularly from nine integrated gene copies of X-33/PINS2 after 90 h under methanol induction. The results indicate that in both expression systems the production level of PGAA is similar but there is a limitation in secretion efficiency.


Assuntos
Microbiologia Industrial/métodos , Penicilina Amidase/metabolismo , Pichia/metabolismo , Proteínas Recombinantes/metabolismo , Achromobacter/genética , Achromobacter/metabolismo , Reatores Biológicos/microbiologia , Clonagem Molecular , Códon/genética , Dosagem de Genes , Expressão Gênica , Vetores Genéticos , Penicilina Amidase/genética , Pichia/genética , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Transformação Genética
6.
Genome Announc ; 4(2)2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27056219

RESUMO

Agrobacteriumsp. strain R89-1 isolated from composted wastes ofPapaver somniferumcan effectively biotransform codeine/morphine into 14-OH-derivatives. Here, we present a 4.7-Mb assembly of the R89-1 strain genome. The draft shows that the strain R89-1 represents a distinct phylogenetic lineage within the genusAgrobacterium.

7.
Bioresour Technol ; 102(17): 7621-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21683578

RESUMO

Production of enantiopure esomeprazole by biocatalysis is of great demand by pharmaceutical industry. A Gram-positive bacterium oxidizing omeprazole sulfide 1a (5-methoxy-2-[((4-methoxy-3,5-dimethylpyridin-2-yl)methyl)thio]-1H-benzoimidazole) to (S)-sulfoxide esomeprazole 2a (S)-5-methoxy-2-[(4-methoxy-3,5-dimethylpyridin-2-yl) methylsulfinyl]-3H-benzoimidazole was isolated from soil polluted with elemental sulfur. The strain exhibited the highest identity with the genus Lysinibacillus and catalyzed oxidation of 1a into enantiopure esomeprazole with conversion of 77% in a stirred bioreactor, fed-batch culture. No consecutive oxidation of (S)-sulfoxide to sulfone was observed during whole-cell catalysis. The unique characteristics of the catalyst provide a solid basis for further improvement and development of sustainable green bioprocess.


Assuntos
Bacillus/metabolismo , Omeprazol/análogos & derivados , Omeprazol/metabolismo , Sequência de Bases , Reatores Biológicos , Biotransformação , Cromatografia em Camada Fina , Meios de Cultura , Primers do DNA , Esomeprazol , Concentração de Íons de Hidrogênio , Oxirredução , Reação em Cadeia da Polimerase , Estereoisomerismo , Temperatura
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