Phenotype of htgA (mbiA), a recently evolved orphan gene of Escherichia coli and Shigella, completely overlapping in antisense to yaaW. Issue 1 (17th October 2013)

• Record Type: Journal Article
• Authors: Fellner, Lea; Bechtel, Niklas; Witting, Michael A.; Simon, Svenja; Schmitt‐Kopplin, Philippe; Keim, Daniel; Scherer, Siegfried; Neuhaus, Klaus
• Is Part Of: FEMS microbiology letters. Volume 350:Issue 1(2014:Jan.)
• Page Start: 57
• Page End: 64
• Publication Date: 2013-10-17
• Subjects: Microbiology -- Periodicals; 579
• DOI: 10.1111/1574-6968.12288
• Languages: English
• ISSNs: 0378-1097

Abstract

<abstract abstract-type="main" id="fml12288-abs-0001"> <title>Abstract</title> <p>Overlapping embedded genes, such as <italic>htgA</italic><italic>/</italic><italic>yaaW</italic>, are assumed to be rare in prokaryotes. In <italic>Escherichia coli </italic>O157:H7, <italic>gfp</italic> fusions of both promoter regions revealed activity and transcription start sites could be determined for both genes. Both <italic>htgA</italic> and <italic>yaaW</italic> were inactivated strand specifically by introducing a stop codon. Both mutants exhibited differential phenotypes in biofilm formation and metabolite levels in a nontargeted analysis, suggesting that both are functional despite YaaW but not HtgA could be expressed. While <italic>yaaW</italic> is distributed all over the <italic>Gammaproteobacteria</italic>, an overlapping <italic>htgA</italic>‐like sequence is restricted to the <italic>Escherichia</italic>‐<italic>Klebsiella</italic> clade. Full‐length <italic>htgA</italic> is only present in <italic>Escherichia</italic> and <italic>Shigella, </italic> and <italic>htgA</italic> showed evidence for purifying selection. Thus, <italic>htgA</italic> is an interesting case of a lineage‐specific, nonessential and young orphan gene.</p> </abstract>