Stabilization of steroid 11-hydroxylation activity ofCunninghamella elegans protoplasts in organic osmotic stabilizers

Dtugoński, J.; Bartnicka, Katarzyna; Chojecka, V.; Sedlaczek, L

doi:10.1007/bf01201948

Cited by 7 publications

(2 citation statements)

References 12 publications

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“…It is worth mentioning that the removal of chitin, an eukaryotic cell wall structure analogous to the prokaryotic peptidoglycan (ROGERS et al 1980), resulted also in greater steroid transformation rate of protoplasts, which has been shown in our previous papers (SEDLACZEK eta/. 1984, DLUGONSKI et al 1992.…”

Section: Discussionsupporting

confidence: 54%

Effect of inhibitors of cell envelope synthesis on β‐sitosterol side chain degradation by Mycobacterium sp. NRRL MB 3683

Sedlaczek

Górmiński

Lisowska

1994

J. Basic Microbiol.

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The role of the lipid bilayer and the peptidoglycan of the mycobacterial cell wall in the permeation of beta-sitosterol into the cell and its transformation to androst-1-ene-3,17-dione (AD) and androsta-1,4-diene-3,17-dione (ADD) was studied. Specific inhibitors were used at concentrations affecting the biosynthesis of the assumed target structures, but causing only partial cell growth inhibition or exerting no effect on growth. m-Fluorophenylalanine and DL-norleucine which are known to disorganize the biosynthesis of amphipatic components of the outer layer of the lipid bilayer, used at concentrations 250 micrograms/ml and 400 micrograms/ml, respectively, increased the formation rate of AD+ADD from 0.3 (control) to 0.7 and 0.8 mg products/g dry weight/h. The disorganization of the underlying mycolyl-arabinogalactan structure by the action of the ethambutol at the concentration 40 micrograms/ml, at which the cell growth was apparently not affected, caused the decrease of the product formation from 135 mg/l to 70 mg/l. In the presence of isoniazid (350 micrograms/ml) only trace amounts of AD accumulated during 48 hours of transformation indicating much lower activity than that of the intact cells. The most effective among the tested inhibitors of peptidoglycan synthesis were glycine (15 mg/ml) and vancomycin (150 micrograms/ml) which enhanced the transformation activity of the treated cells nearly three times. Increased transformation rate was also obtained by the action of colistin at concentrations ranging from 10 micrograms/ml to 15 micrograms/ml.

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Section: Discussionsupporting

confidence: 54%

Effect of inhibitors of cell envelope synthesis on β‐sitosterol side chain degradation by Mycobacterium sp. NRRL MB 3683

Sedlaczek

Górmiński

Lisowska

1994

J. Basic Microbiol.

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“…Several studies have been reported on immobilization techniques applied to filamentous fungi (Pakula and Freeman 1996;Dlugonski et al 1997) but little is known about the potential of biofilms (Harding et al 2009). Pakula and Freeman (1996) showed that a stainless steel mesh was required to catch mycelium fragments and start a gradual biofilm development in a continuous biofilm bioreactor for an oil-degrading filamentous fungus, Tyromyces sambuceus.…”

Section: Resultsmentioning

confidence: 99%

Filamentous fungal biofilm for production of human drug metabolites

Amadio

Casey

Murphy

2013

Appl Microbiol Biotechnol

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In drug development access to drug metabolites is essential for assessment of toxicity and pharmacokinetic studies. Metabolites are usually acquired via chemical synthesis, although biological production is potentially more efficient with fewer waste management issues. A significant problem with the biological approach is the effective half-life of the biocatalyst, which can be resolved by immobilisation. The fungus Cunninghamella elegans is well established as a model of mammalian metabolism, although it has not yet been used to produce metabolites on a large scale. Here we describe immobilisation of C. elegans as a biofilm, which can transform drugs to important human metabolites. The biofilm was cultivated on hydrophilic microtiter plates and in shake flasks containing a steel spring in contact with the glass. Fluorescence and confocal scanning laser microscopy revealed that the biofilm was composed of a dense network of hyphae, and biochemical analysis demonstrated that the matrix was predominantly polysaccharide. The medium composition 2 was crucial for both biofilm formation and biotransformation of flurbiprofen. In shake flasks the biofilm transformed 86 % of the flurbiprofen added to hydroxylated metabolites within 24 h, which was slightly more than planktonic cultures (76 %). The biofilm had a longer effective lifetime than the planktonic cells, which underwent lysis after 2 × 72 h cycles, and diluting the Sabouraud dextrose broth enabled the thickness of the biofilm to be controlled while retaining transformation efficiency. Thus, C. elegans biofilm has the potential to be applied as a robust biocatalyst for the production of human drug metabolites required for drug development.3

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