Phenotype MicroArrays are ideally suited to the study of transporters. Loss of function mutations in amino acid or peptide transporters result in negative tests for metabolic substrates the mutant fails to import. Knock-out strains of drug efflux transporters exhibit hypersensitivity to inhibitory chemicals that may be substrates of the transporter. Similarly, overexpression of an efflux transporter may result in relative resistance to the inhibitors. Phenotype MicroArray technology can be used to assay transporter function, assign substrates to transporters, and quickly identify multidrug resistance. The papers below show some of the ways that transporters have been studied with Biolog’s Phenotype MicroArray technology.
Homologs of the Acinetobacter baumannii AceI Transporter Represent a New Family of Bacterial Multidrug Efflux Sytems
Proteins homologous to AceI (Acinetobacter Chlorhexidine Efflux) were expressed and their resistance profiles were examined. Phenotype MicroArray MicroPlates 11-20 were used to explore substrate recognition profiles.
Role of Transcription Factor NimR (YeaM) in Sensitivity Control of Escherichia coli to 2-nitroimidazole
YeaN, an MFS tranporter, was found to be under the control of the YeaM transcription factor. Phenotype MicroArray analysis indicated that YeaN confers resistance to 2-nitroimadazole (2-NI), and suggests that YeaN plays a role in 2-NI efflux. A YeaN knockout strain was found to have a relative growth defect in media containing 2-NI. YeaN was renamed NimT (for nitroimadazole transport).
High-Throughput Screening of Dipeptide Utilization Mediated by the ABC Transporter DppBCDF and its Substrate-Binding Proteins DppA1-A5 in Pseudomonas aeruginosa
Di- and tri-peptides on PM6,7,8 were used to probe the peptide transport systems of P. aeruginosa. Side-chain properties of substrates were included in the analysis. The DppBCDF transporter and DppA1-A5 subtrate binding proteins were characterized for substrate specificity and a substrate profile was created for the permease.
Phenotype MicroArray Technology
Biolog’s Phentoype MicroArray technology enables researchers to evaluate nearly 2000 phenotypes of a microbial cell in a single experiment. This integrated system of cellular assays, instrumentation and bioinformatics software provides cellular knowledge that complements molecular information, helping you interpret and find the relevant aspects in massive amounts of gene expression or proteomics data. Through comprehensive and precise quantitation of phenotypes, researchers are able to obtain an unbiased perspective of the effect on cells of genetic differences, environmental change, exposure to chemicals or drugs, and more.