Please use this identifier to cite or link to this item:
Title: Pneumococcal galactose catabolism is controlled by multiple regulators acting on pyruvate formate lyase
Authors: Al-Bayati, Firas A. Y.
Kahya, Hasan F. H.
Damianou, Andreas
Shafeeq, Sulman
Kuipers, Oscar P.
Andrew, Peter W.
Yesilkaya, Hasan
First Published: 27-Feb-2017
Publisher: Nature Publishing Group
Citation: Scientific Reports, 2017, 7, Article number: 43587
Abstract: Catabolism of galactose by Streptococcus pneumoniae alters the microbe's metabolism from homolactic to mixed acid fermentation, and this shift is linked to the microbe's virulence. However, the genetic basis of this switch is unknown. Pyruvate formate lyase (PFL) is a crucial enzyme for mixed acid fermentation. Functional PFL requires the activities of two enzymes: pyruvate formate lyase activating enzyme (coded by pflA) and pyruvate formate lyase (coded by pflB). To understand the genetic basis of mixed acid fermentation, transcriptional regulation of pflA and pflB was studied. By microarray analysis of ΔpflB, differential regulation of several transcriptional regulators were identified, and CcpA, and GlnR's role in active PFL synthesis was studied in detail as these regulators directly interact with the putative promoters of both pflA and pflB, their mutation attenuated pneumococcal growth, and their expression was induced on host-derived sugars, indicating that these regulators have a role in sugar metabolism, and multiple regulators are involved in active PFL synthesis. We also found that the influence of each regulator on pflA and pflB expression was distinct in terms of activation and repression, and environmental condition. These results show that active PFL synthesis is finely tuned, and feed-back inhibition and activation are involved.
DOI Link: 10.1038/srep43587
eISSN: 2045-2322
Version: Publisher Version
Status: Peer-reviewed
Type: Journal Article
Rights: Copyright © the authors, 2017. This is an open-access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Appears in Collections:Published Articles, Dept. of Infection, Immunity and Inflammation

Files in This Item:
File Description SizeFormat 
srep43587.pdfPublished (publisher PDF)1.74 MBAdobe PDFView/Open

Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.