A novel Serratia sp. ZS6 isolate derived from petroleum sludge secretes biosurfactant and lipase in medium with olive oil as sole carbon source

SUMMARYWild-type strains ofAspergillus nidulansgrow poorly onL-histidine as a sole nitrogen source. The synthesis of the enzyme histidase (EC. 4.3.1.3) appears to be a limiting factor in the growth of the wild type, as strains carrying the mutantareA102 allele have elevated histidase levels and grow strongly on histidine as a sole nitrogen source.L-Histidine is an extremely weak sole carbon source for all strains.Ammonium repression has an important role in the regulation of histidase synthesis and the relief of ammonium repression is dependent on the availability of a good carbon source. The level of histidase synthesis does not respond to the addition of exogenous substrate.Mutants carrying lesions in thesarA orsarB loci (suppressor ofareA102) have been isolated. The growth properties of these mutants on histidine as a sole nitrogen source correlate with the levels of histidase synthesized. Mutation at thesarA andsarB loci also reduces the utilization of a number of other nitrogen sources. The data suggest that these two genes may code for regulatory products involved in nitrogen catabolism. No histidase structural gene mutants were identified and possible explanations of this are discussed.

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Isolation of alcohol oxidase and two other methanol regulatable genes from the yeast Pichia pastoris

Molecular and Cellular Biology ◽

10.1128/mcb.5.5.1111-1121.1985 ◽

1985 ◽

Vol 5 (5) ◽

pp. 1111-1121

Author(s):

S B Ellis ◽

P F Brust ◽

P J Koutz ◽

A F Waters ◽

M M Harpold ◽

...

Keyword(s):

Pichia Pastoris ◽

Carbon Source ◽

Sole Carbon Source ◽

Alcohol Oxidase ◽

Methylotrophic Yeasts ◽

Sequence Analyses ◽

Yeast Pichia Pastoris ◽

Oxidation Of Methanol ◽

Regulated Expression

The oxidation of methanol follows a well-defined pathway and is similar for several methylotrophic yeasts. The use of methanol as the sole carbon source for the growth of Pichia pastoris stimulates the expression of a family of genes. Three methanol-responsive genes have been isolated; cDNA copies have been made from mRNAs of these genes, and the protein products from in vitro translations have been examined. The identification of alcohol oxidase as one of the cloned, methanol-regulated genes has been made by enzymatic, immunological, and sequence analyses. Methanol-regulated expression of each of these three isolated genes can be demonstrated to occur at the level of transcription. Finally, DNA subfragments of two of the methanol-responsive genomic clones from P. pastoris have been isolated and tentatively identified as containing the control regions involved in methanol regulation.

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Review for "Preparation, statistical optimization and characterization of poly (3-hydroxybutyrate) fermented by Cupriavidus nector utilizing various hydrolysates of alligator weed ( Alternanthera philoxeroides ) as a sole carbon source"

10.1002/btpr.2992/v2/review1 ◽

2020 ◽

Author(s):

Petrovici Roxana

Keyword(s):

Carbon Source ◽

Sole Carbon Source ◽

Statistical Optimization ◽

Alternanthera Philoxeroides ◽

Alligator Weed

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