scholarly journals Catabolite repression in the gram-positive bacteria: Generation of negative regulators of transcription

1993 ◽  
Vol 51 (1) ◽  
pp. 25-28 ◽  
Author(s):  
George C. Stewart
2015 ◽  
Vol 25 (2-3) ◽  
pp. 79-93 ◽  
Author(s):  
Joseph W. Lengeler

<b><i>Past:</i></b> The title ‘PTS 50 or The PTS after 50 years' relies on the first description in 1964 of the phosphoenolpyruvate-dependent carbohydrate:phosphotransferase system (PTS) by Kundig, Gosh and Roseman [Proc Natl Acad Sci USA 1964;52:1067-1074]. The system comprised proteins named Enzyme I, HPr and Enzymes II, as part of a novel PTS for carbohydrates in Gram-negative and Gram-positive bacteria, whose ‘biological significance remained unclear'. In contrast, studies which would eventually lead to the discovery of the central role of the PTS in bacterial metabolism had been published since before 1942. They are primarily linked to names like Epps and Gale, J. Monod, Cohn and Horibata, and B. Magasanik, and to phenomena like ‘glucose effects', ‘diauxie', ‘catabolite repression' and carbohydrate transport. <b><i>Present:</i></b> The pioneering work from Roseman's group initiated a flood of publications. The extraordinary progress from 1964 to this day in the qualitative and in vitro description of the genes and enzymes of the PTS, and of its multiple roles in global cellular control through ‘inducer exclusion', gene induction and ‘catabolite repression', in cellular growth, in cell differentiation and in chemotaxis, as well as the differences of its functions between Gram-positive and Gram-negative bacteria, was one theme of the meeting and will not be treated in detail here. <b><i>Future:</i></b> At the 1988 Paris meeting entitled ‘The PTS after 25 years', Saul Roseman predicted that ‘we must describe these interactions [of the PTS components] in a quantitative way [under] in vivo conditions'. I will present some results obtained by our group during recent years on the old phenomenon of diauxie by means of very fast and quantitative tests, measured in vivo, and obtained from cultures of isogenic mutant strains growing under chemostat conditions. The results begin to hint at the problems relating to future PTS research, but also to the ‘true science' of Roseman.


2003 ◽  
Vol 67 (4) ◽  
pp. 475-490 ◽  
Author(s):  
Jessica B. Warner ◽  
Juke S. Lolkema

SUMMARY Carbon catabolite repression (CCR) by transcriptional regulators follows different mechanisms in gram-positive and gram-negative bacteria. In gram-positive bacteria, CcpA-dependent CCR is mediated by phosphorylation of the phosphoenolpyruvate:sugar phosphotransferase system intermediate HPr at a serine residue at the expense of ATP. The reaction is catalyzed by HPr kinase, which is activated by glycolytic intermediates. In this review, the distribution of CcpA-dependent CCR among bacteria is investigated by searching the public databases for homologues of HPr kinase and HPr-like proteins throughout the bacterial kingdom and by analyzing their properties. Homologues of HPr kinase are commonly observed in the phylum Firmicutes but are also found in the phyla Proteobacteria, Fusobacteria, Spirochaetes, and Chlorobi, suggesting that CcpA-dependent CCR is not restricted to gram-positive bacteria. In the α and β subdivisions of the Proteobacteria, the presence of HPr kinase appears to be common, while in the γ subdivision it is more of an exception. The genes coding for the HPr kinase homologues of the Proteobacteria are in a gene cluster together with an HPr-like protein, termed XPr, suggesting a functional relationship. Moreover, the XPr proteins contain the serine phosphorylation sequence motif. Remarkably, the analysis suggests a possible relation between CcpA-dependent gene regulation and the nitrogen regulation system (Ntr) found in the γ subdivision of the Proteobacteria. The relation is suggested by the clustering of CCR and Ntr components on the genome of members of the Proteobacteria and by the close phylogenetic relationship between XPr and NPr, the HPr-like protein in the Ntr system. In bacteria in the phylum Proteobacteria that contain HPr kinase and XPr, the latter may be at the center of a complex regulatory network involving both CCR and the Ntr system.


2004 ◽  
Vol 1697 (1-2) ◽  
pp. 123-135 ◽  
Author(s):  
Sandrine Poncet ◽  
Ivan Mijakovic ◽  
Sylvie Nessler ◽  
Virginie Gueguen-Chaignon ◽  
Vincent Chaptal ◽  
...  

Microbiology ◽  
1996 ◽  
Vol 142 (2) ◽  
pp. 217-230 ◽  
Author(s):  
M. H. Saier ◽  
S. Chauvaux ◽  
G. M. Cook ◽  
J. Deutscher ◽  
I. T. Paulsen ◽  
...  

1997 ◽  
Vol 161 ◽  
pp. 491-504 ◽  
Author(s):  
Frances Westall

AbstractThe oldest cell-like structures on Earth are preserved in silicified lagoonal, shallow sea or hydrothermal sediments, such as some Archean formations in Western Australia and South Africa. Previous studies concentrated on the search for organic fossils in Archean rocks. Observations of silicified bacteria (as silica minerals) are scarce for both the Precambrian and the Phanerozoic, but reports of mineral bacteria finds, in general, are increasing. The problems associated with the identification of authentic fossil bacteria and, if possible, closer identification of bacteria type can, in part, be overcome by experimental fossilisation studies. These have shown that not all bacteria fossilise in the same way and, indeed, some seem to be very resistent to fossilisation. This paper deals with a transmission electron microscope investigation of the silicification of four species of bacteria commonly found in the environment. The Gram positiveBacillus laterosporusand its spore produced a robust, durable crust upon silicification, whereas the Gram negativePseudomonas fluorescens, Ps. vesicularis, andPs. acidovoranspresented delicately preserved walls. The greater amount of peptidoglycan, containing abundant metal cation binding sites, in the cell wall of the Gram positive bacterium, probably accounts for the difference in the mode of fossilisation. The Gram positive bacteria are, therefore, probably most likely to be preserved in the terrestrial and extraterrestrial rock record.


Author(s):  
B.K. Ghosh

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.


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