RESUMO
A 55-year-old man was scheduled for resection of an adrenal tumor under the diagnosis of a non-functioning adrenal tumor. He was admitted for unstable angina 58 days preoperatively, and on the second hospital day, he had an episode of ventricular tachycardia for 20 seconds following epigastric pain. Abdominal computed tomography scans revealed a retroperitoneal abscess, which was subsequently drained effectively, and a right adrenal tumor. Because of the almost normal plasma catecholamine concentration, the tumor was considered a nonfunctioning tumor. However, when the surgeon manipulated the tumor during the operation, the patient's blood pressure increased suddenly to 240/120 mmHg. The hypertensive crisis was managed with nicardipine and phentolamine. After resection of the tumor, his blood pressure decreased to 80/40 mmHg, and the patient was treated with ephedrine, phenylephrine, and noradrenaline. After surgery, the tumor was confirmed histopathologically as a pheochromocytoma. The management of patients with a hypertensive crisis under suspicion of pheochromocytoma is discussed.
Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Anestesia , Feocromocitoma/cirurgia , Neoplasias das Glândulas Suprarrenais/diagnóstico , Anti-Hipertensivos/administração & dosagem , Humanos , Hipertensão/tratamento farmacológico , Cuidados Intraoperatórios , Complicações Intraoperatórias/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Nicardipino/administração & dosagem , Fentolamina/administração & dosagem , Feocromocitoma/diagnósticoRESUMO
Genes involved in the degradation of fluorene to phthalate were characterized in the fluorene degrader Terrabacter sp. strain DBF63. The initial attack on both fluorene and 9-fluorenone was catalyzed by DbfA to yield 9-fluorenol and 1,1a-dihydroxy-1-hydro-9-fluorenone, respectively. The FlnB protein exhibited activities against both 9-fluorenol and 1,1a-dihydroxy-1-hydro-9-fluorenone to produce 9-fluorenone and 2'-carboxy-2,3-dihydroxybiphenyl, respectively. FlnD is a heteromeric protein encoded by flnD1 and ORF16, being a member of the class III two-subunit extradiol dioxygenase. FlnE was identified as a serine hydrolase for the meta-cleavage products that yield phthalate.
Assuntos
Actinomycetales/genética , Actinomycetales/metabolismo , Fluorenos/metabolismo , Genes Bacterianos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/fisiologia , Biodegradação Ambiental , Compostos de Bifenilo/metabolismo , Catecóis/metabolismo , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Ordem dos Genes , Genes Bacterianos/genética , Genes Bacterianos/fisiologia , Hidrolases/genética , Hidrolases/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Dados de Sequência Molecular , Oxirredutases/genética , Oxirredutases/metabolismo , Oxigenases/genética , Oxigenases/metabolismo , Ácidos Ftálicos/metabolismo , Análise de Sequência de DNA , Homologia de Sequência , SinteniaRESUMO
Methylobacillus sp. strain 12S produces an exopolysaccharide (EPS), methanolan, composed of glucose, mannose and galactose. Twenty-four ORFs flanking a Tn5 insertion site in an EPS-deficient mutant were identified, and 21 genes (epsCBAKLDEFGHIJMNOPQRSTU) were predicted to participate in methanolan synthesis on the basis of the features of the primary sequence. Gene disruption analyses revealed that epsABCEFGIJNOP and epsR are required for methanolan synthesis, whereas epsKD and epsH are not essential. EpsFG and EpsE showed homology with Wzc (chain length regulator) and Wza (export protein) of group 1 capsule-producing Escherichia coli, suggesting that methanolan was synthesized via a Wzy-like biosynthesis system. This possibility was supported by the fact that the putative hydropathy profiles of EpsH and EpsM were similar to those of Wzx and Wzy, which are also involved in the flipping of the repeating unit in the cytoplasmic membrane and the polymerization of the capsule in the Wzy-dependent system. EpsBJNOP and EpsR are probably glycosyltransferases involved in the synthesis of the repeating unit onto the lipid carrier. In particular, EpsB appeared to catalyse the initial transfer of the glucose moiety. On the basis of their predicted location in the cells, it is proposed that EpsI and EpsL are involved in methanolan export to the cell surface. E. coli strains expressing EpsQ, EpsS and EpsT showed enhanced activities of GDP-mannose pyrophosphorylase, UDP-galactose 4-epimerase and UDP-glucose pyrophosphorylase, respectively, revealing that they were responsible for the production of the activated compositional sugars of methanolan. EpsU contains a conserved a lytic transglycosylase motif, indicating that it could participate in the degradation of polysaccharides. EpsA and EpsK, which have conserved DNA-binding and cAMP-binding motifs, respectively, were deduced to be transcriptional regulators. In particular, EpsA seems to positively regulate the transcription of methanolan synthesis genes, since the constitutive expression of epsA in strain 12S increased the EPS production. Interestingly, EpsD showed homology with peptidyl prolyl cis-trans isomerases that catalyse the folding of proteins following translocation across the cytoplasmic membrane.
Assuntos
Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Methylobacillus/metabolismo , Polissacarídeos Bacterianos/biossíntese , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Methylobacillus/enzimologia , Methylobacillus/genética , Dados de Sequência Molecular , Fases de Leitura Aberta , Alinhamento de Sequência , Análise de Sequência de DNA , Transcrição Gênica , Transformação BacterianaRESUMO
2-Hydroxy-6-oxo-6-(2(')-aminophenyl)-hexa-2,4-dienoate hydrolases (CarC enzymes) from two carbazole-degrading bacteria were purified using recombinant Escherichia coli strains with the histidine (His)-tagged purification system. The His-tagged CarC (ht-CarC) enzymes from Pseudomonas resinovorans strain CA10 (ht-CarC(CA10)) and Janthinobacterium sp. strain J3 (ht-CarC(J3)) exhibited hydrolase activity toward 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate as the purified native CarC(CA10) did. ht-CarC(J3) was crystallized in the space group I422 with cell dimensions of a=b=130.3A, c=84.5A in the hexagonal setting, and the crystal structure of ht-CarC(J3) was determined at 1.86A resolution. The final refined model of ht-CarC(J3) yields an R-factor of 21.6%, although the electron-density corresponding to Ile146 to Asn155 was ambiguous in the final model. We compared the known structures of BphD from Rhodococcus sp. strain RHA1 and CumD from Pseudomonas fluorescens strain IP01. The backbone conformation of ht-CarC(J3) was better superimposed with CumD than with BphD(RHA1). The side-chain directions of Arg185 and Trp262 residues in the substrate binding pockets of these enzymes were different among these proteins, suggesting that these residues may take a conformational change during the catalytic cycles.
Assuntos
Oxirredutases/química , Oxirredutases/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Sequência de Aminoácidos , Bactérias/enzimologia , Carbazóis , Clonagem Molecular , Cristalografia por Raios X , Primers do DNA , Escherichia coli/enzimologia , Escherichia coli/genética , Histidina , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Conformação Proteica , Subunidades Proteicas/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sitios de Sequências RotuladasRESUMO
Effects of lead nitrate (LN), a hepatic mitogen, on hepatic gene expressions of lanosterol 14alpha-demethylase (CYP51) and the sterol regulatory element binding proteins (SREBP-1a, SREBP-1c and SREBP-2), which are thought to be transcription factors for hepatic CYP51 gene, were examined by the methods of Northern blot and/or real time reverse transcriptase-polymerase chain reaction (RT-PCR). In both immature (4-week-old) and mature (7-week-old) rats, LN treatment resulted in definite increases in hepatic gene expression of CYP51 at 12 h and in the liver weight at 48 h. As for transcription factors for the CYP51 gene, enhanced gene expression of SREBP-2 was observed 6-12 h after LN treatment, whereas no enhanced gene expression of other SREBPs, SREBP-1a and SREBP-1c, was observed at any time after the treatment; for SREBP-1a, there was no significant change; for SREPB-1c, there was a drastic decrease. In addition, the serum total cholesterol level was increased 12 h after LN treatment to 7-week-old rats, and the increased level was maintained at least up to 48 h later. In the present study, we demonstrate for the first time that LN, a heavy-metal ion, activates the expression of the SREBP-2 and CYP51 genes without decreasing the serum total cholesterol level and further suggest that only SREBP-2 among SREBPs might play an important role in the LN-enhanced CYP51 gene expression.