scholarly journals Identification and Characterization of a Bacterial Transport System for the Uptake of Pyruvate, Propionate, and Acetate in Corynebacterium glutamicum

2008 ◽  
Vol 191 (3) ◽  
pp. 940-948 ◽  
Author(s):  
Elena Jolkver ◽  
Denise Emer ◽  
Stefan Ballan ◽  
Reinhard Krämer ◽  
Bernhard J. Eikmanns ◽  
...  
Keyword(s):  
Corynebacterium Glutamicum ◽  
Transport System ◽  
Natural Habitat ◽  
Negative Control ◽  
Bacterial Cells ◽  
Biotechnological Production ◽  
Proton Potential ◽  
Secondary Transporter ◽  
Identification And Characterization

ABSTRACT The metabolism of monocarboxylic acids is of central importance for bacteria in their natural habitat as well as during biotechnological production. Although biosynthesis and degradation are well understood, the transport of such compounds is still a matter of discussion. Here we present the identification and characterization of a new transport system in Corynebacterium glutamicum with high affinity for acetate and propionate and with lower affinity for pyruvate. Biochemical analysis of this monocarboxylic acid transporter (MctC) revealed for the first time a quantitative discrimination of passive diffusion and active transport of acetate by bacterial cells. MctC is a secondary transporter and belongs to the class of sodium solute symporters, but it is driven by the electrochemical proton potential. The mctC gene is preceded by and cotranscribed with cg0952, a locus encoding a small membrane protein, and the transcription of the cg0952-mctC operon is under the control of the transcriptional regulators RamA and RamB. Both of these proteins directly bind to the promoter region of the operon; RamA is essential for expression and RamB exerts a slightly negative control on expression of the cg0952-mctC operon. mctC expression is induced in the presence of pyruvate and beneficial under substrate-limiting conditions for C. glutamicum.

scholarly journals Identification and characterization of PorH, a new cell wall channel of Corynebacterium glutamicum

2005 ◽  
Vol 1715 (1) ◽  
pp. 25-36 ◽  
Author(s):  
Peter Hünten ◽  
Noelia Costa-Riu ◽  
Dieter Palm ◽  
Friedrich Lottspeich ◽  
Roland Benz
Keyword(s):  
Cell Wall ◽  
Corynebacterium Glutamicum ◽  
Identification And Characterization

scholarly journals Identification and Characterization of Nip, Necrosis-Inducing Virulence Protein of Erwinia carotovora subsp. carotovora

2004 ◽  
Vol 17 (12) ◽  
pp. 1366-1375 ◽  
Author(s):  
Laura Mattinen ◽  
Marina Tshuikina ◽  
Andres Mäe ◽  
Minna Pirhonen
Keyword(s):  
Leaf Tissue ◽  
Erwinia Carotovora ◽  
Soft Rot ◽  
Bacterial Cells ◽  
Virulence Determinants ◽  
Virulence Protein ◽  
Encoding Gene ◽  
Rot Disease ◽  
Identification And Characterization

Erwinia carotovora subsp. carotovora is a gram-negative bacterium that causes soft rot disease of many cultivated crops. When a collection of E. carotovora subsp. carotovora isolates was analyzed on a Southern blot using the harpin-encoding gene hrpN as probe, several harpinless isolates were found. Regulation of virulence determinants in one of these, strain SCC3193, has been characterized extensively. It is fully virulent on potato and in Arabidopsis thaliana. An RpoS (SigmaS) mutant of SCC3193, producing elevated levels of secreted proteins, was found to cause lesions resembling the hypersensitive response when infiltrated into tobacco leaf tissue. This phenotype was evident only when bacterial cells had been cultivated on solid minimal medium at low pH and temperature. The protein causing the cell death was purified and sequenced, and the corresponding gene was cloned. The deduced sequence of the necrosis-inducing protein (Nip) showed homology to necrosis- and ethylene-inducing elicitors of fungi and oomycetes. A mutant strain of E. carotovora subsp. carotovora lacking the nip gene showed reduced virulence in potato tuber assay but was unaffected in virulence in potato stem or on other tested host plants.

scholarly journals Alternative ORFs and small ORFs: shedding light on the dark proteome

2019 ◽  
Vol 48 (3) ◽  
pp. 1029-1042 ◽  
Author(s):  
Mona Wu Orr ◽  
Yuanhui Mao ◽  
Gisela Storz ◽  
Shu-Bing Qian
Keyword(s):  
Genetic Information ◽  
Open Reading Frame ◽  
Bacterial Cells ◽  
Reading Frame ◽  
Protein Encoding ◽  
Future Work ◽  
Encoding Genes ◽  
Small Orfs ◽  
Identification And Characterization

Abstract Traditional annotation of protein-encoding genes relied on assumptions, such as one open reading frame (ORF) encodes one protein and minimal lengths for translated proteins. With the serendipitous discoveries of translated ORFs encoded upstream and downstream of annotated ORFs, from alternative start sites nested within annotated ORFs and from RNAs previously considered noncoding, it is becoming clear that these initial assumptions are incorrect. The findings have led to the realization that genetic information is more densely coded and that the proteome is more complex than previously anticipated. As such, interest in the identification and characterization of the previously ignored ‘dark proteome’ is increasing, though we note that research in eukaryotes and bacteria has largely progressed in isolation. To bridge this gap and illustrate exciting findings emerging from studies of the dark proteome, we highlight recent advances in both eukaryotic and bacterial cells. We discuss progress in the detection of alternative ORFs as well as in the understanding of functions and the regulation of their expression and posit questions for future work.

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