Subsystem: Deoxyribose and Deoxynucleoside Catabolism
This subsystem's description is:
Numerous bacteria can use the 2-deoxy-D-ribosyl moiety of 2'-deoxyribonucleosides as the sole carbon and energy source. Genetic and biochemical studies, using Escherichia coli and Salmonella enterica serovar Typhimurium as model organisms, have shown that the catabolic pathway involves four enzymes: thymidine phosphorylase (EC 126.96.36.199), purine nucleoside phosphorylase (EC 188.8.131.52), phosphopentomutase (EC 184.108.40.206), and deoxyriboaldolase (EC 220.127.116.11), encoded by the deoA, deoD, deoB, and deoC genes, respectively. In both organisms the four genes are organized as an operon( the deoCABD operon).
The operon is transcribed from two promoters located 600 bp apart. Transcription initiation of the operon is highly regulated by a complex interplay of three regulatory proteins, of which two, DeoR and CytR, are repressors and the third is the cAMP-receptor protein (CAP). The genes encoding these proteins are unlinked to each other and to the deoCABD operon. The internal inducer for expression of the operon is 2-deoxy-D-ribose 5-phosphate (dRib5P) inactivating DeoR and cytidine (in S. enterica also uridine) inactivating CytR.
1.0 - Deoxyribose and Deoxynucleoside catabolism as in Escherichia coli (the deoCABD operon);
2.0 - Deoxyribonucleosides utilization as in B.subtilis (DeoD,DeoB,DeoC are nesessary);
3.0 - Deoxyribose catabolism only as in Synechococcus (DeoK and DeoC);
X - variant with missing genes, not clear which one yet.
For more information, please check out the description and the additional notes tabs, below
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