Regulation of tricarboxylate transport and metabolism in ADP1.

Despite the significant presence of plant-derived tricarboxylic acids in some environments, few studies detail the bacterial metabolism of -aconitic acid (Taa) and tricarballylic acid (Tcb). In a soil bacterium, ADP1, we discovered interrelated pathways for the consumption of Taa and Tcb. An intricate regulatory scheme tightly controls the transport and catabolism of both compounds and may reflect that they can be toxic inhibitors of the tricarboxylic acid cycle.

Engineering CatM, a LysR-Type Transcriptional Regulator, to Respond Synergistically to Two Effectors.

The simultaneous response of one transcriptional regulator to different effectors remains largely unexplored. Nevertheless, such interactions can substantially impact gene expression by rapidly integrating cellular signals and by expanding the range of transcriptional responses. In this study, similarities between paralogs were exploited to engineer novel responses in CatM, a regulator that controls benzoate degradation in ADP1.

Malonate degradation in ADP1: operon organization and regulation by MdcR.

Transcriptional regulators in the LysR or GntR families are typically encoded in the genomic neighbourhood of bacterial genes for malonate degradation. While these arrangements have been evaluated using bioinformatics methods, experimental studies demonstrating co-transcription of predicted operons were lacking. Here, transcriptional regulation was characterized for a cluster of genes that enable a soil bacterium, ADP1, to use malonate as a carbon source.

Analysis of IS1236-mediated gene amplification events in Acinetobacter baylyi ADP1.

Recombination between insertion sequence copies can cause genetic deletion, inversion, or duplication. However, it is difficult to assess the fraction of all genomic rearrangements that involve insertion sequences. In previous gene duplication and amplification studies of Acinetobacter baylyi ADP1, an insertion sequence was evident in approximately 2% of the characterized duplication sites.

Genome-wide selection for increased copy number in Acinetobacter baylyi ADP1: locus and context-dependent variation in gene amplification.

Renewed interest in gene amplification stems from its importance in evolution and a variety of medical problems ranging from drug resistance to cancer. However, amplified DNA segments (amplicons) are not fully characterized in any organism. Here we report a novel Acinetobacter baylyi system for genome-wide studies.