Andreas Haldimann

TL;DR: A series of powerful and versatile conditional-replication, integration, and modular (CRIM) plasmids that encode different forms of resistance and can be used together in the same cell for stable expression of complex metabolic or regulatory pathways from diverse sources are developed.

TL;DR: Several new cloning vectors for mutagenesis and allele replacement experiments are described, including plasmids that have the R6K gamma DNA replication origin so they replicate only in bacteria supplying the pi replication protein, and which also encode a positive counterselectable marker.

TL;DR: By using P(araB)-phoB+, P(rhaB)- phoB+ or P-rhaB-phoR+ fusions, this work was able to overcome the extremely deleterious growth defect of a Pst+ delta phoU mutant and indicates that less PhoR than PhoB is required for transcriptional activation of the Pho regulon, which is consistent with their respective modes of action.

TL;DR: An Escherichia coli K-12 model system was developed for studying the VanS-VanR two-component regulatory system required for high-level inducible vancomycin resistance in Enterococcus faecium BM4147 and it was demonstrated that the response regulator VanR activates PvanH, but not PvanR, expression upon activation (phosphorylation) by the partner kinase VanS.

TL;DR: The overall genetic strategy described here may be useful for studying interactions of other components of the vancomycin resistance and P1 signal transduction pathways, other two-component regulatory systems, and other interacting proteins.