RRC ID 48173
Author McCarthy S, Johnson T, Pavlik BJ, Payne S, Schackwitz W, Martin J, Lipzen A, Keffeler E, Blum P.
Title Expanding the Limits of Thermoacidophily in the Archaeon Sulfolobus solfataricus by Adaptive Evolution.
Journal Appl Environ Microbiol
Abstract Extremely thermoacidophilic Crenarchaeota belonging to the order Sulfolobales flourish in hot acidic habitats that are strongly oxidizing. The pH extremes of these habitats, however, often exceed the acid tolerance of type species and strains. Here, adaptive laboratory evolution was used over a 3-year period to test whether such organisms harbor additional thermoacidophilic capacity. Three distinct cell lines derived from a single type species were subjected to high-temperature serial passage while culture acidity was gradually increased. A 178-fold increase in thermoacidophily was achieved after 29 increments of shifted culture pH resulting in growth at pH 0.8 and 80°C. These strains were named super-acid-resistant Crenarchaeota (SARC). Mathematical modeling using growth parameters predicted the limits of acid resistance, while genome resequencing and transcriptome resequencing were conducted for insight into mechanisms responsible for the evolved trait. Among the mutations that were detected, a set of eight nonsynonymous changes may explain the heritability of increased acid resistance despite an unexpected lack of transposition. Four multigene components of the SARC transcriptome implicated oxidative stress as a primary challenge accompanying growth at acid extremes. These components included accelerated membrane biogenesis, induction of the mer operon, and an increased capacity for the generation of energy and reductant.
Volume 82(3)
Pages 857-67
Published 2016-2-1
DOI 10.1128/AEM.03225-15
PII AEM.03225-15
PMID 26590281
PMC PMC4725277
MeSH Adaptation, Physiological Archaeal Proteins / genetics Archaeal Proteins / metabolism Biotechnology Directed Molecular Evolution* Genome, Bacterial Hot Temperature* Hydrogen-Ion Concentration Models, Biological Multigene Family Mutation Operon Oxidation-Reduction Oxidative Stress / genetics Sequence Analysis, DNA Sulfolobus solfataricus / genetics* Sulfolobus solfataricus / growth & development Sulfolobus solfataricus / physiology* Time Factors Transcriptome
IF 4.016
Times Cited 19
Resource
General Microbes JCM 30930