The change of peroxidase and catalase enzyme activity in submerged cultures of Penicillium chrysogenum

The filamentous fungus Penicillium chrysogenum (recently reidentified as Penicillium rubens) is used in the industrial production of the b-lactam antibiotic penicillin. There are several mechanisms regulating the production of this antibiotic, acting both at the genetic and epigenetic levels, the latter including the modification of chromatin by methyltransferases. S-adenosyl-L-methionine (AdoMet) is the main donor of methyl groups for methyltransferases. In addition, it also acts as a donor of aminopropyl groups during the biosynthesis of polyamines. AdoMet is synthesized from L-methionine and ATP by AdoMet-synthetase. In silico analysis of the P. chrysogenum genome revealed the presence of a single gene (Pc16g04380) encoding a putative protein with high similarity to well-known AdoMet-synthetases. Due to the essential nature of this gene, functional analysis was carried out using RNAi-mediated silencing techniques. Knock-down transformants exhibited a decrease in AdoMet, S-adenosyl-L-homocysteine (AdoHcy), spermidine and benzylpenicillin levels, whereas they accumulated a yellow-orange pigment in submerged cultures. On the other hand, overexpression led to reduced levels of benzylpenicillin, thereby suggesting that the AdoMet synthetase, in addition to participate in primary metabolism, also controls secondary metabolism in P. chrysogenum.

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Solid state fermentation for the production of α-amylase from Penicillium chrysogenum using mixed agricultural by-products as substrate

Biologia ◽

10.2478/s11756-006-0137-2 ◽

2006 ◽

Vol 61 (6) ◽

Cited By ~ 13

Author(s):

Figen Ertan ◽

Bilal Balkan ◽

Seda Balkan ◽

Tulin Aktac

Keyword(s):

Enzyme Activity ◽

Solid State ◽

Solid State Fermentation ◽

Penicillium Chrysogenum ◽

Enzyme Production ◽

Solid Substrate ◽

Inoculum Level ◽

Fermentation Conditions ◽

The Individual ◽

By Products

AbstractProduction of α-amylase from local isolate, Penicillium chrysogenum, under solid-state fermentation (SSF) was carried out in this study. Different agricultural by-products, such as wheat bran (WB), sunflower oil meal (SOM), and sugar beet oil cake (SBOC), were used as individual substrate for the enzyme production. WB showed the highest enzyme activity (750 U/gds). Combination of WB, SOM, and SBOC (1:3:1 w/w/w) resulted in a higher enzyme yield (845 U/gds) in comparison with the use of the individual substrate. This combination was used as mixed solid substrate for the production of α-amylase from P. chrysogenum by SSF. Fermentation conditions were optimized. Maximum enzyme yield (891 U/gds) was obtained when SSF was carried out using WB + SOM + SBOC (1:3:1 w/w/w), having initial moisture of 75%, inoculum level of 20%, incubation period of 7 days at 30°C. Galactose (1% w/w), urea and peptone (1% w/w), as additives, caused increase in the enzyme activity.

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Pellet formation and fragmentation in submerged cultures of Penicillium chrysogenum and its relation to penicillin production

Biotechnology Progress ◽

10.1021/bp00031a013 ◽

1995 ◽

Vol 11 (1) ◽

pp. 93-98 ◽

Cited By ~ 92

Author(s):

Jens Nielsen ◽

Claus L. Johansen ◽

Michael Jacobsen ◽

Preben Krabben ◽

John Villadsen

Keyword(s):

Penicillium Chrysogenum ◽

Penicillin Production ◽

Submerged Cultures ◽

Pellet Formation

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Morphological and biochemical analyses of changes in rat hepatocytes related to wine and ethanol consumption

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111276 ◽

1984 ◽

Vol 42 ◽

pp. 232-233

Author(s):

S.M. Geyer ◽

C.L. Mendenhall ◽

J.T. Hung ◽

E.L. Cardell ◽

R.L. Drake ◽

...

Keyword(s):

Electron Microscopy ◽

Endoplasmic Reticulum ◽

Enzyme Activity ◽

Malic Enzyme ◽

Smooth Endoplasmic Reticulum ◽

Rat Hepatocytes ◽

Mature Male ◽

Treatment Groups ◽

Malic Enzyme Activity ◽

Biochemical Analyses

Thirty-three mature male Holtzman rats were randomly placed in 3 treatment groups: Controls (C); Ethanolics (E); and Wine drinkers (W). The animals were fed synthetic diets (Lieber type) with ethanol or wine substituted isocalorically for carbohydrates in the diet of E and W groups, respectively. W received a volume of wine which provided the same gram quantity of alcohol consumed by E. The animals were sacrificed by decapitation after 6 weeks and the livers processed for quantitative triglycerides (T3), proteins, malic enzyme activity (MEA), light microscopy (LM) and electron microscopy (EM). Morphometric analysis of randomly selected LM and EM micrographs was performed to determine organellar changes in centrilobular (CV) and periportal (PV) regions of the liver. This analysis (Table 1) showed that hepatocytes from E were larger than those in C and W groups. Smooth endoplasmic reticulum decreased in E and increased in W compared to C values.

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