Gene expression profiling of Thermoplasma volcanium under extreme stress conditions

Identifying the stress response mechanisms in Archaea mighthave potential applications considering the industrial importanceof their enzymes. In this study, as an extension of our researchon anti-stress mechanisms, we have carried out genome widetranscriptome analysis ofThermoplasma volcanium(grows opti-mally at pH 2.7 and 60◦C) under extreme stress (i.e., heat- shockat 68◦C, hydrogen peroxide, 0.03 mM H2O2and pH stress atpH 5.0) using AgilentCustom Gene Expression Microarray.The data was analyzed by using GeneSpring Ver 12.6 Software. With a pH shift from 2.7 to 5.0 most of the gene expressionwas repressed: of 47 genes differentially expressed by≥2-fold,66% were up-regulated and 34% were down-regulated. Among thenotably induced genes, some code for membrane proteins, sugarand amino acid transporters, cation transporter and antiporterswhich are crucial for maintaining cellular pH homeostasis. Oxida-tive stress mostly resulted in decreased gene expression; out of 452genes expressions of which changed≥2 fold, 75% were down regu-lated. Up regulation of ferrodoxins, oxidoreductases, thioredoxin,Fe-S oxidoreductases, aldo/keto reductases and dehydrogenases asa response to H2O2may be important for maintaining intracellularredox potentials and detoxifications. Temperature up-shift favoredthe expression of heat-shock proteins (including GroEL, sHSP, DnaK, DnaJ, GrpE) as well as genes related to carbohydrate metabolism(e.g., sugar permease).
Citation Formats
S. Kocabıyık, “Gene expression profiling of Thermoplasma volcanium under extreme stress conditions,” presented at the European Biotechnology Congress (22 - 26 Haziran 2014), Edinburgh, Saint Helena, 2014, Accessed: 00, 2021. [Online]. Available: