Hat this (partly) reflects differences in the complement of WhiJ-like signal transduction cascades. The strikingly reduced number of paralogues in S. venezuelae (one of several streptomycetes that lack a cluster orthologous to whiJ itself) may underpin the ability of S. venezuelae to sporulate exceptionally readily and comprehensively even in submerged culture, which has led to its adoption as a m
Ehalf of the Federation of European Microbiological SocietiesG. Chandra K.F. ChaterTable 2. Streptomyces genes or gene clusters that frequently contain TTA codons* SCO number of gene *asterisk means TTA codons are absent from the S. coelicolor gene 0381*;0382*;0383 0683*;0684*;0685* Fraction of TTA-containing orthologues among 14 Streptomyces genomes (see note) 6/12; 5/9; 2/10 2/12; 4/13; 2/Func
Itive search for orthologues of the 147 S. coelicolor TTA-containing genes (or in some cases gene clusters). We identified 19 that were widespread and frequently TTA-containing in 13 other Streptomyces genomes (Table 2). In addition, a further 10 genes or gene clusters frequently had TTA codons, even though their S. coelicolor orthologues were TTA-free (asterisks in Table 2). As 27/29 of the TTA-c
This general class were present in the ur-actinobacterium, giving rise to the possibility of subtle control of sigma factor activity by signals that might include morphological checkpoints (as in the case of the spoIIAA/spoIIAB genes of B. subtilis; PiggotHilbert, 2004) or stress (as in the case of sigB of B. subtilis; Price, 2000). Indeed, BldG influences the activity of the stress-responsive sig
There is little evidence of direct regulatory interplay between the two genes. Possibly, then, AdpA evolved to regulate aspects of developmental physiology complementary to those regulated by BldN (if so, one might anticipate that some cross-checks between the two regulons will eventually be discovered). The regulation of adpA in streptomycetes is remarkably complex (reviewed in detail in Liu et a
Nd their TTA codons have adaptive value to streptomycetes and not to other actinobacteria. As shown in Table 2, about half of these genes encode proteins likely to be closely implicated in gene regulation or signal transduction, although their targets are mostly unknown. They include five conserved paralogues of genes found in the whiJ cluster (see below for further discussion) and gene sets for h
There is little evidence of direct regulatory interplay between the two genes. Possibly, then, AdpA evolved to regulate aspects of developmental physiology complementary to those regulated by BldN (if so, one might anticipate that some cross-checks between the two regulons will eventually be discovered). The regulation of adpA in streptomycetes is remarkably complex (reviewed in detail in Liu et a
Translation (Nguyen et al., 2003; Takano et al., 2003). Translational regulation is via a very rare UUA codon in the adpA mRNA, falling between the segments encoding the two domains of AdpA. UUA is the only one of the six leucine codons to comprise only A and U residues, so the corresponding TTA codon is comparatively rare in GC-rich genomes ?it occurs in only 147 chromosomal genes in S. coelicolo