BioProject

The goal of this analysis is to define the aerobic and anaerobic regulons for the transcription factor Mlc (Makes Large Colonies) in the periodontal pathogen Aggregatibacter actinomycetemcomitans. More...

The goal of this analysis is to define the aerobic and anaerobic regulons for the transcription factor Mlc (Makes Large Colonies) in the periodontal pathogen Aggregatibacter actinomycetemcomitans. The objectives were met by comparing the mRNA profile of a wild type strain, JP2, to that of an isogenic mutant deleted of the Mlc gene. Both strains were grown aerobically and anaerobically. The results show that Mlc is involved in the regulation of dozens of genes in both growth conditions. Overall design: Half of the study (anaerobic samples) was a four biological replicates study using total RNA recovered from four separate anaerobic cultures of wild-type Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans strain JP2 and four separate anaerobic cultures of strain AAM155, an isogenic deletion mutant in which the gene for Mlc (Makes Large Colonies) has been replaced by a spectinomycin resistance gene cassette. The cells were grown anaerobically in pairs (wild type paired with mutant). The second half of the study (aerobic samples) was a four biological replicates study using total RNA recovered from four separate aerobic cultures of wild-type Aggregatibacter actinomycetemcomitans strain JP2 and four separate anaerobic cultures of strain AAM155, an isogenic deletion mutant of Mlc. The cells were grown aerobically in pairs (wild type paired with mutant). Each chip measures the expression level of 2,116 genes from A. actinomycetemcomitans strain HK1651. There were 11 different 60-mer probes /gene for 94% of the genes, and the entire probe set (22,537 probes) was replicated (technical replicates) three times on each array. Each probe set is contained on a quarter of a chip and there were also 4,426 random probes per array. A total of four chips were used in these experiments. Less...