Nutritive Medium Engineering Enhanced Production of Extracellular Lipase by Trichoderma Longibrachiatum

The release of cytochrome c from mitochondria during apoptosis results in the enhanced production of superoxide radicals, which are converted to H2O2 by Mn-superoxide dismutase. We have been concerned with the role of cytochrome c/H2O2 in the induction of oxidative stress during apoptosis. Our initial studies showed that cytochrome c is a potent catalyst of 2′,7′-dichlorofluorescin oxidation, thereby explaining the increased rate of production of the fluorophore 2′,7′-dichlorofluorescein in apoptotic cells. Although it has been speculated that the oxidizing species may be a ferryl-haem intermediate, no definitive evidence for the formation of such a species has been reported. Alternatively, it is possible that the hydroxyl radical may be generated, as seen in the reaction of certain iron chelates with H2O2. By examining the effects of radical scavengers on 2′,7′-dichlorofluorescin oxidation by cytochrome c/H2O2, together with complementary EPR studies, we have demonstrated that the hydroxyl radical is not generated. Our findings point, instead, to the formation of a peroxidase compound I species, with one oxidizing equivalent present as an oxo-ferryl haem intermediate and the other as the tyrosyl radical identified by Barr and colleagues [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503]. Studies with spin traps indicated that the oxo-ferryl haem is the active oxidant. These findings provide a physico-chemical basis for the redox changes that occur during apoptosis. Excessive changes (possibly catalysed by cytochrome c) may have implications for the redox regulation of cell death, including the sensitivity of tumour cells to chemotherapeutic agents.

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Molecular reidentification of human pathogenic Trichoderma isolates as Trichoderma longibrachiatum and Trichoderma citrinoviride

Medical Mycology ◽

10.1046/j.1365-280x.1999.00197.x ◽

1999 ◽

Vol 37 (1) ◽

pp. 25-33 ◽

Cited By ~ 2

Author(s):

K. KUHLS ◽

E. LIECKFELDT ◽

T. BORNER ◽

E. GUEHO

Keyword(s):

Trichoderma Longibrachiatum ◽

Trichoderma Citrinoviride ◽

Trichoderma Isolates

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Effect of explant's size and phytohormonal composition of nutritive medium on post-vitification recovery of garlic meristems

Problems of Cryobiology and Cryomedicine ◽

10.15407/cryo25.01.013 ◽

2015 ◽

Vol 25 (1) ◽

pp. 13-23

Author(s):

Mariya V. Shevchenko ◽

◽

Aleksandr N. Sukach ◽

Keyword(s):

Nutritive Medium

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Enhanced production, purification, and characterization of propionicin PLG-1, a bacteriocin produced by Propionibacterium thoenii P127

10.31274/rtd-180813-11288 ◽

1995 ◽

Author(s):

Hyun-Dong Paik

Keyword(s):

Purification And Characterization ◽

Enhanced Production ◽

Propionibacterium Thoenii

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IMPACT OF SORBITOL- INDUCED OSMOTIC STRESS ON SOME BIOCHEMICAL TRAITS OF POTATO IN VITRO

IRAQI JOURNAL OF AGRICULTURAL SCIENCES ◽

10.36103/ijas.v51i4.1082 ◽

2020 ◽

Vol 51 (4) ◽

pp. 1038-1047

Author(s):

Mawia & et al.

Keyword(s):

Ascorbic Acid ◽

Osmotic Stress ◽

Cytoplasmic Membrane ◽

Genotypic Variation ◽

Membrane Damage ◽

Membrane Integrity ◽

Culture Collection ◽

Nutritive Medium ◽

Starting Point

This study had as principal objective identification of osmotic-tolerant potato genotypes by using "in vitro" tissue culture and sorbitol as a stimulating agent, to induce water stress, which was added to the culture nutritive medium in different concentration (0,50, 110, 220, 330 and 440 mM). The starting point was represented by plantlets culture collection, belonging to eleven potato genotypes: Barcelona, Nectar, Alison, Jelly, Malice, Nazca, Toronto, Farida, Fabulla, Colomba and Spunta. Plantlets were multiplied between two internodes to obtain microcuttings (in sterile condition), which were inoculated on medium. Sorbitol-induced osmotic stress caused a significant reduction in the ascorbic acid, while the concentration of proline, H2O2 and solutes leakage increased compared with the control. Increased the proline content prevented lipid peroxidation, which played a pivotal role in the maintenance of membrane integrity under osmotic stress conditions. The extent of the cytoplasmic membrane damage depends on osmotic stress severity and the genotypic variation in the maintenance of membranes stability was highly associated with the ability of producing more amounts of osmoprotectants (proline) and the non-enzymic antioxidant ascorbic acid in response to osmotic stress level. The results showed that the genotypes Jelly, Nectar, Allison, Toronto, and Colomba are classified as highly osmotic stress tolerant genotypes, while the genotypes Nazca and Farida are classified as osmotic stress susceptible ones.

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