scholarly journals Expression of the Laccase Gene from a White Rot Fungus in Pichia pastoris Can Enhance the Resistance of This Yeast to H2O2-Mediated Oxidative Stress by Stimulating the Glutathione-Based Antioxidative System

2012 ◽  
Vol 78 (16) ◽  
pp. 5845-5854 ◽  
Author(s):  
Yang Yang ◽  
Fangfang Fan ◽  
Rui Zhuo ◽  
Fuying Ma ◽  
Yangmin Gong ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Pichia Pastoris ◽  
Oxidative Damage ◽  
White Rot ◽  
Antioxidative System ◽  
White Rot Fungus ◽  
Laccase Gene ◽  
Content Type ◽  
Glutamylcysteine Synthetase

ABSTRACTLaccase is a copper-containing polyphenol oxidase that has great potential in industrial and biotechnological applications. Previous research has suggested that fungal laccase may be involved in the defense against oxidative stress, but there is little direct evidence supporting this hypothesis, and the mechanism by which laccase protects cells from oxidative stress also remains unclear. Here, we report that the expression of the laccase gene from white rot fungus inPichia pastoriscan significantly enhance the resistance of yeast to H2O2-mediated oxidative stress. The expression of laccase in yeast was found to confer a strong ability to scavenge intracellular H2O2and to protect cells from lipid oxidative damage. The mechanism by which laccase gene expression increases resistance to oxidative stress was then investigated further. We found that laccase gene expression inPichia pastoriscould increase the level of glutathione-based antioxidative activity, including the intracellular glutathione levels and the enzymatic activity of glutathione peroxidase, glutathione reductase, and γ-glutamylcysteine synthetase. The transcription of the laccase gene inPichia pastoriswas found to be enhanced by the oxidative stress caused by exogenous H2O2. The stimulation of laccase gene expression in response to exogenous H2O2stress further contributed to the transcriptional induction of the genes involved in the glutathione-dependent antioxidative system, includingPpYAP1,PpGPX1,PpPMP20,PpGLR1, andPpGSH1. Taken together, these results suggest that the expression of the laccase gene inPichia pastoriscan enhance the resistance of yeast to H2O2-mediated oxidative stress by stimulating the glutathione-based antioxidative system to protect the cell from oxidative damage.

Melanoidin-containing wastewaters induce selective laccase gene expression in the white-rot fungus Trametes sp. I-62

2008 ◽  
Vol 159 (2) ◽  
pp. 103-109 ◽  
Author(s):  
Tania González ◽  
María Carmen Terrón ◽  
Susana Yagüe ◽  
Howard Junca ◽  
José María Carbajo ◽  
...  
Keyword(s):  
Gene Expression ◽  
White Rot ◽  
White Rot Fungus ◽  
Laccase Gene

scholarly journals Differential Gene Expression in Pycnoporus coccineus during Interspecific Mycelial Interactions with Different Competitors

2013 ◽  
Vol 79 (21) ◽  
pp. 6626-6636 ◽  
Author(s):  
Yonathan Arfi ◽  
Anthony Levasseur ◽  
Eric Record
Keyword(s):  
Gene Expression ◽  
Differential Gene Expression ◽  
Differentially Expressed ◽  
White Rot ◽  
White Rot Fungus ◽  
Content Type ◽  
Mold Fungus ◽  
Wide Range ◽  
Differential Gene ◽  
Pycnoporus Coccineus

ABSTRACTFungi compete against each other for environmental resources. These interspecific combative interactions encompass a wide range of mechanisms. In this study, we highlight the ability of the white-rot fungusPycnoporus coccineusto quickly overgrow or replace a wide range of competitor fungi, including the gray-mold fungusBotrytis cinereaand the brown-rot fungusConiophora puteana. To gain a better understanding of the mechanisms deployed byP. coccineusto compete against other fungi and to assess whether common pathways are used to interact with different competitors, differential gene expression inP. coccineusduring cocultivation was assessed by transcriptome sequencing and confirmed by quantitative reverse transcription-PCR analysis of a set of 15 representative genes. Compared with the pure culture, 1,343 transcripts were differentially expressed in the interaction withC. puteanaand 4,253 were differentially expressed in the interaction withB. cinerea, but only 197 transcripts were overexpressed in both interactions. Overall, the results suggest that a broad array of functions is necessary forP. coccineusto replace its competitors and that different responses are elicited by the two competitors, although a portion of the mechanism is common to both. However, the functions elicited by the expression of specific transcripts appear to converge toward a limited set of roles, including detoxification of secondary metabolites.

Chemoprotective Effects of Propolis on Aflatoxin B1-Induced Hepatotoxicity in Rats: Oxidative Damage and Hepatotoxicity by Modulating TP53, Oxidative Stress

2020 ◽  
Vol 17 (3) ◽  
pp. 191-199
Author(s):  
Seval Yilmaz ◽  
Fatih Mehmet Kandemir ◽  
Emre Kaya ◽  
Mustafa Ozkaraca
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Oxidative Damage ◽  
Aflatoxin B1 ◽  
Tp53 Gene ◽  
Control Group ◽  
Glutathione S Transferase ◽  
Gene Expressions ◽  
Cat Gene ◽  
Gst Activity

Objective: This study aimed to detect hepatic oxidative damage caused by aflatoxin B1 (AFB1), as well as to examine how propolis protects against hepatotoxic effects of AFB1. Method: Rats were split into four groups as control group, AFB1 group, propolis group, AFB1+ propolis group. Results: There was significant increase in malondialdehyde (MDA) level and tumor suppressor protein (TP53) gene expression, Glutathione (GSH) level, Catalase (CAT) activity, CAT gene expression decreased in AFB1 group in blood. MDA level and Glutathione-S-Transferase (GST) activity, GST and TP53 gene expressions increased in AFB1 group, whereas GSH level and CAT activity alongside CAT gene expression decreased in liver. AFB1+propolis group showed significant decrease in MDA level, GST activity, TP53 and GST gene expressions, GSH level and CAT activity and CAT gene expression increased in liver compared to AFB1 group. Conclusion: These results suggest that propolis may potentially be natural agent that prevents AFB1- induced oxidative stress and hepatotoxicity.

scholarly journals Effects of glutamine supplementation on oxidative stress-related gene expression and antioxidant properties in rats with streptozotocin-induced type 2 diabetes

2011 ◽  
Vol 107 (8) ◽  
pp. 1112-1118 ◽  
Author(s):  
Pei-Hsuan Tsai ◽  
Jun-Jen Liu ◽  
Chui-Li Yeh ◽  
Wan-Chun Chiu ◽  
Sung-Ling Yeh
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Amino Acid ◽  
Oxidative Damage ◽  
Antioxidant Capacity ◽  
Enzyme Activities ◽  
Antioxidant Enzyme Activities ◽  
Related Gene ◽  
Gene Expressions ◽  
Oxidative Stress Related Gene

There are close links among hyperglycaemia, oxidative stress and diabetic complications. Glutamine (GLN) is an amino acid with immunomodulatory properties. The present study investigated the effect of dietary GLN on oxidative stress-relative gene expressions and tissue oxidative damage in diabetes. There were one normal control (NC) and two diabetic groups in the present study. Diabetes was induced by an intraperitoneal injection of nicotinamide followed by streptozotocin (STZ). Rats in the NC group were fed a regular chow diet. In the two diabetic groups, one group (diabetes mellitus, DM) was fed a common semi-purified diet while the other group received a diet in which part of the casein was replaced by GLN (DM-GLN). GLN provided 25 % of total amino acid N. The experimental groups were fed the respective diets for 8 weeks, and then the rats were killed for further analysis. The results showed that blood thioredoxin-interacting protein (Txnip) mRNA expression in the diabetic groups was higher than that in the NC group. Compared with the DM group, the DM-GLN group had lower glutamine fructose-6-phosphate transaminase 1, a receptor of advanced glycation end products, and Txnip gene expressions in blood mononuclear cells. The total antioxidant capacity was lower and antioxidant enzyme activities were altered by the diabetic condition. GLN supplementation increased antioxidant capacity and normalised antioxidant enzyme activities. Also, the renal nitrotyrosine level and Txnip mRNA expression were lower when GLN was administered. These results suggest that dietary GLN supplementation decreases oxidative stress-related gene expression, increases the antioxidant potential and may consequently attenuate renal oxidative damage in rats with STZ-induced diabetes.

The Effect of Heavy Metal-Induced Oxidative Stress on the Enzymes in White Rot Fungus Phanerochaete chrysosporium

2014 ◽  
Vol 175 (3) ◽  
pp. 1281-1293 ◽  
Author(s):  
Qihua Zhang ◽  
Guangming Zeng ◽  
Guiqiu Chen ◽  
Min Yan ◽  
Anwei Chen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Heavy Metal ◽  
Phanerochaete Chrysosporium ◽  
White Rot ◽  
White Rot Fungus

scholarly journals Differential regulation of γ-glutamylcysteine synthetase heavy and light subunit gene expression

1997 ◽  
Vol 326 (1) ◽  
pp. 167-172 ◽  
Author(s):  
Jiaxin CAI ◽  
Zong-Zhi HUANG ◽  
Shelly C. LU
Keyword(s):  
Oxidative Stress ◽  
Gene Expression ◽  
Steady State ◽  
Mrna Level ◽  
Rat Hepatocytes ◽  
Mrna Levels ◽  
Subunit Gene ◽  
Subunit Mrna ◽  
Glutamylcysteine Synthetase ◽  
Steady State Mrna Level

γ-Glutamylcysteine synthetase (GCS) is the rate-limiting enzyme in the biosynthesis of glutathione and is composed of a heavy and a light subunit. Although the heavy subunit is enzymically active alone, the light subunit plays an important regulatory role by making the holoenzyme function more efficiently. In the current study we examined whether conditions which are known to influence gene expression of the heavy subunit also influence that of the light subunit, and the mechanisms involved. Treatment of cultured rat hepatocytes with hormones such as insulin and hydrocortisone, or plating hepatocytes under low cell density increased the steady-state mRNA level of the heavy subunit only. Treatment with diethyl maleate (DEM), buthionine sulphoximine (BSO) and t-butylhydroquinone (TBH) increased the steady state mRNA level and gene transcription rates of both subunits. These treatments share in common their ability to induce oxidative stress and activate nuclear factor κB (NF-κB). Treatment with protease inhibitors 7-amino-1-chloro-3-tosylamido-2-heptanone (TLCK) or L-1-tosylamido-2-phenylethyl chloromethyl ketone (TPCK) had no influence on the basal NF-κB and GCS subunit mRNA levels, but blocked the activation of NF-κB by DEM, BSO and TBH, and the increase in GCS heavy subunit mRNA level by BSO and TBH. On the other hand, the DEM-, BSO- and TBH-induced increase in GCS light-subunit mRNA level was unaffected by TLCK and TPCK. Thus only the heavy subunit is hormonally regulated and growth sensitive, whereas both subunits are regulated by oxidative stress. Signalling through NF-κB is involved only in the oxidative-stress-mediated changes in the heavy subunit gene expression.

Sign in / Sign up

Export Citation Format

Share Document