Disease relevance of fadL

• New locus (ttr) in Escherichia coli K-12 affecting sensitivity to bacteriophage T2 and growth on oleate as the sole carbon source [1].
• The receptor affected by ttr was the major receptor used by phage T2 and was located in the outer membrane [1].

High impact information on fadL

• The fadL insertion mutant H5 was defective for long-chain fatty acid transport but bound oleic acid at significant levels [2].
• The hexameric insertion at the SalI site (fadL allele termed S1; insertion after amino acid 410) conferred an Oleslow phenotype and resulted in a reduction of long-chain fatty acid transport (36% the wild-type level) [2].
• Kinetics of the utilization of medium and long chain fatty acids by mutant of Escherichia coli defective in the fadL gene [3].
• We demonstrated repression of fadL transcription and activation of fabA transcription in vitro using run-off transcription assays containing purified FadR and RNA polymerase [4].
• The promoter and untranslated leader within fadL had two binding sites for FadR, OL1 at -25 to -9 and OL2 at -1 to +16 relative to the start of transcription [4].

Chemical compound and disease context of fadL

• The genes for 1,2-propanediol degradation (pdu) and B12 synthesis (cob), along with the genes for sulfur reduction (ttr, phs, and asr), constitute more than 1% of the Salmonella genome and are all absent from E. coli [5].

Biological context of fadL

• The most likely explanation is that fadL and ttr are in an operon and that ttr encodes an outer membrane protein which functions in translocating long-chain fatty acids across the outer membrane and also as a receptor for phage T2 [1].
• We determined the nucleotide sequence of a 2.8-kb chromosomal DNA segment that contains the fadL gene [6].
• Osmoregulation of the fatty acid receptor gene fadL in Escherichia coli [7].

Other interactions of fadL

• It was found that mutational alterations at two loci, ompF (encoding the outer membrane protein OmpF) and ttr (T-two resistance), are needed to give full resistance to phage T2 [1].
• Similarly, E. coli fadR mutants were used alone and in conjunction with fadA, fadB, and fadL mutants to show that the effect of the fadR mutation is dependent on fadB+ and fadA+ gene products [8].
• As expected, fadL-phoA fusions were unable to grow on oleate plates because the outer membrane-bound fatty acid transport protein FadL was defective [9].

References