Anaerobic glyoxylate cycle activity during simultaneous utilization of glycogen and acetate in uncultured Accumulibacter enriched in enhanced biological phosphorus removal communities

Burow, Luke C., Mabbett, Amanda N. and Blackall, Linda L. (2008) Anaerobic glyoxylate cycle activity during simultaneous utilization of glycogen and acetate in uncultured Accumulibacter enriched in enhanced biological phosphorus removal communities. The ISME Journal, 2 10: 1040-1051. doi:10.1038/ismej.2008.45


Author Burow, Luke C.
Mabbett, Amanda N.
Blackall, Linda L.
Title Anaerobic glyoxylate cycle activity during simultaneous utilization of glycogen and acetate in uncultured Accumulibacter enriched in enhanced biological phosphorus removal communities
Journal name The ISME Journal   Check publisher's open access policy
ISSN 1751-7362
Publication date 2008-10-01
Year available 2008
Sub-type Article (original research)
DOI 10.1038/ismej.2008.45
Open Access Status
Volume 2
Issue 10
Start page 1040
End page 1051
Total pages 12
Place of publication New York
Publisher The Nature publishing Group
Language eng
Subject C1
969999 Environment not elsewhere classified
060504 Microbial Ecology
Abstract Enhanced biological phosphorus removal (EBPR) communities protect waterways from nutrient pollution and enrich microorganisms capable of assimilating acetate as polyhydroxyalkanoate (PHA) under anaerobic conditions. Accumulibacter, an important uncultured polyphosphate-accumulating organism (PAO) enriched in EBPR, was investigated to determine the central metabolic pathways responsible for producing PHA. Acetate uptake and assimilation to PHA in Accumulibacter was confirmed using fluorescence in situ hybridization (FISH)-microautoradiography and post-FISH chemical staining. Assays performed with enrichments of Accumulibacter using an inhibitor of glyceraldehyde-3-phosphate dehydrogenase inferred anaerobic glycolysis activity. Significant decrease in anaerobic acetate uptake and PHA production rates were observed using inhibitors targeting enzymes within the glyoxylate cycle. Bioinformatic analysis confirmed the presence of genes unique to the glyoxylate cycle (isocitrate lyase and malate synthase) and gene expression analysis of isocitrate lyase demonstrated that the glyoxylate cycle is likely involved in PHA production. Reduced anaerobic acetate uptake and PHA production was observed after inhibition of succinate dehydrogenase and upregulation of a succinate dehydrogenase gene suggested anaerobic activity. Cytochrome b/b6 activity inferred that succinate dehydrogenase activity in the absence of external electron acceptors may be facilitated by a novel cytochrome b/b6 fusion protein complex that pushes electrons uphill to more electronegative electron carriers. Identification of phosphoenolpyruvate carboxylase and phosphoenolpyruvate carboxykinase genes in Accumulibacter demonstrated the potential for interconversion of C3 intermediates of glycolysis and C4 intermediates of the glyoxylate cycle. Our findings along with previous hypotheses from analysis of microbiome data and metabolic models for PAOs were used to develop a model for anaerobic carbon metabolism in Accumulibacter.
Keyword polyphosphate-accumulating organism
polyhydroxyalkanoate
quantitative reverse-transcriptase PCR
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ
Additional Notes published online 11 September 2008

Document type: Journal Article
Sub-type: Article (original research)
Collections: 2009 Higher Education Research Data Collection
Advanced Water Management Centre Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 25 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 24 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Wed, 08 Apr 2009, 01:49:08 EST by Suzanne Read on behalf of Advanced Water Management Centre