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Articles one is entitled not to read!
This section [Online March 20, 2009] lists Escherichia coli adenylate cyclase-connected articles which raise suspicion concerning the review process. The data are either poor or not interpreted properly. In some cases interpretation of data lacks understanding of prior work. In worst cases data are manipulated, if not falsified, as to fit an agenda. In any case these articles would not have appeared in their present form if reviewers had been both responsible and unbiased!
May 22, 2009
Pyruvate kinase-deficient Escherichia coli exhibits increased plasmid
copy number and cyclic AMP levels
Authors: Drew S. Cunningham, Zhu Liu, Nathan Domagalski, Richard R. Koepsel,
Mohammad M. Ataai, and Michael M. Domach
Journal of Bacteriology 2009, 191(9): 3041
Discussion reads: 'Prior work also indicated that PL8UV5 is about fourfold stronger than Plac when both are compared for growth on glucose (21)'. Reference (21) [JB] does indeed describe lac up-promoter mutants including PUV5 but none of the mutants carry the L8 mutation. And in a repeat performance: 'As a second control, Plac in PB25 was mutated to PL8UV5, which is cAMP insensitive and about fourfold stronger than Plac when these two promoters are compared for growth on either glucose-6-phosphate (37) or glucose (21)'. In yet another example of citation violation, Discussion reads: '… glucose- 6-phosphate … is similar to glucose in repressive strength (29)'. Not quite, see Table 1 in Reference (29) [Science].
April 17, 2009
Involvement of the Cra global regulatory protein in the expression of the iscRSUA operon, revealed during studies of tricarballylate catabolism in Salmonella enterica
Authors: Jeffrey A. Lewis, Jeffrey M. Boyd, Diana M. Downs and Jorge C. Escalante-Semerena
Journal of Bacteriology 2009, 191(7): 2069
Connection with Escherichia coli adenylate cyclase: In E. coli the fructose repressor (FruR also known as Cra) indirectly controls cAMP levels under specific conditions
Material and Methods section reads: 'Skovran et al. previously reported that an isc mutant required nicotinic acid and thiamine for growth. The requirements for these nutrients were bypassed by using overnight cultures grown in LB, without washing the cells, to inoculate fresh medium'. This is incorrect experimental procedure which leads to false data.
March 20, 2009
cAMP does not have an important role in carbon catabolite repression of the Escherichia coli lac operon Author: Atul Narang
Nature Reviews Microbiology 2009, 7(3): 250
It is unethical for Atul Narang to use the data from an article by Wanner et al. and ignore their statement that 'Much of the variation [in β-galactosidase synthesis] was eliminated by growing E. coli in the presence of cAMP, and this component we call cAMP-mediated catabolite repression' [JB]. It is fraudulent to use the data by Wanner et al. to let the reader believe that data in Figure 1A are best fitted with a curve showing that 'to a first approximation, the β-galactosidase activity of exponentially growing cells is inversely proportional to the specific growth rate'. Readers of the correspondence are urged to read the article by Wanner et al. and compare their data to Atul Narang's re-illustration of the same data. Finally it is irresponsible for Atul Narang to ignore the reasoning of a previous correspondence [Medline] to discard the role of cAMP in the glucose-lactose diauxie.
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