Carbohydrate hydrolysis and transport in the extreme thermoacidophile Sulfolobus solfataricus

Sreedevi Lalithambika, Landon Peterson, Karl Dana, Paul Blum

Research output: Contribution to journalArticle

5 Scopus citations

Abstract

Extremely thermoacidophilic microbes, such as Sulfolobus solfataricus, are strict chemoheterotrophs despite their geologic niche. To clarify their ecophysiology, the overlapping roles of endoglucanases and carbohydrate transporters were examined during growth on soluble cellodextrins as the sole carbon and energy source. Strain-specific differences in genome structure implied a unique role for one of three endogenous endoglucanases. Plasmid-based endoglucanase expression promoted the consumption of oligosaccharides, including cellohexaose (G6) through cellonanaose (G9). Protein transporters required for cellodextrin uptake were identified through mutagenesis and complementation of an ABC transporter cassette, including a putative oligosaccharide binding protein. In addition, ablation of the binding protein compromised growth on glucose and alpha-linked oligosaccharides while inactivation of a previously described glucose transporter had no apparent impact. These data demonstrate that S. solfataricus employs a redundant mechanism for soluble cellodextrin catabolism having both substrate uptake and extracytoplasmic hydrolytic components.

Original languageEnglish (US)
Pages (from-to)7931-7938
Number of pages8
JournalApplied and environmental microbiology
Volume78
Issue number22
DOIs
Publication statusPublished - Nov 1 2012

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ASJC Scopus subject areas

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology
  • Ecology

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