Ligninolytic fungus Polyporus sp. S133 mediated metabolic degradation of fluorene.

This study aimed to investigate the impact of nonionic surfactants on the efficacy of fluorine degradation by Polyporus sp. S133 in a liquid culture. Fluorene was observed to be degraded in its entirety by Polyporus sp.

Mechanism of triphenylmethane Cresol Red degradation by Trichoderma harzianum M06.

Cresol Red belongs to the triphenylmethane (TPM) class of dyes which are potentially carcinogenic or mutagenic. However, very few studies on biodegradation of Cresol Red were investigated as compared to other type dyes such as azo and anthraquinone dye. The aim of this work is to evaluate triphenylmethane dye Cresol Red degradation by fungal strain isolated from the decayed wood in Johor Bahru, Malaysia.

An extracellular sensor and an extracellular induction component are required for alkali induction of alkyl hydroperoxide tolerance in Escherichia coli.

Escherichia coli K12 transferred from pH 7.0 to pH 9.0 gains alkylhydroperoxide (AHP) tolerance.

Induction of the PhoE porin by NaCl as the basis for salt-induced acid sensitivity in Escherichia coli.

Organisms grown in low salt broth (LSB) are acid resistant but become sensitive on growth for 30-60 min with 300 mmol l-1 added NaCl. Salt-induced acid sensitivity only occurs in relA+ strains and sensitization is abolished by glucose, this catabolite repression effect being reversed by cAMP. The finding that sensitization did not occur in a phoE strain but did occur in a phoE+ derivative of it suggested that the response might result from PhoE induction, since PhoE acts as the major outer membrane (OM) proton pore under most conditions.

Regulatory aspects of alkali tolerance induction in Escherichia coli.

Escherichia coli shifted from external pH (pH(O)) 7.0 to pH(O) 8.5-9.

Sensitization to acid induced by sodium ions in Escherichia coli: dependence of (p)ppGpp and cAMP and suppression of the relA-associated defect by mutations in envZ.

NaCl-induced acid sensitivity is not a response to high osmotic pressure but is triggered by a high internal sodium ion concentration, evidenced by the finding that conditions which enhance Na+ influx or reduce Na+ efflux, led to increased internal Na+ and allowed induction at lower external sodium ion concentrations and that induction could occur with no osmotic upshock. NaCl-induced acid sensitivity was not observed in Escherichia coli strain MC4100 and its relA lesion was investigated as a possible cause. Transformation of this strain and two other relA mutants to relA+ allowed sensitization by NaCl and whereas strain CF1648 (relA+) was sensitized, its relA deletion derivative was not.