Possible Interaction: Phenylalanine and Serine

“Molecular models were generated for the envelope protein indicating that the amino acid alteration PHE 306 SER could contribute to a different folding in this region located within the domain III.”

“Ionic interactions were also suggested because peptide-VKD protein binding … in ionic strength or pH. Mutagenesis of Cys343 to Ser … Phe resulted in 7–11-fold decreases in vitamin K epoxidation and peptide (EEL) substrate … analysis showed 5–6-fold increases in K m values for the Glu substrate.”

“Replacement of phenylalanine with serine at this site led to the appearance of an intermediate during refolding that lacked secondary structure for both proteins that was not detected for either parental protein.”

“Adding L-serine to L-phenylalanine reduced the uptake only in cortex and hippocampus.”

“Drug cytotoxicity and drug transport assays carried out in the presence of verapamil or progesterone suggest that the Ser to Phe substitution also reduces the capacity of these two reversal agents to modulate P-gp activity.”

“Abstract Ala, Cys, and Ser inhibited rat intestinal transport of 1 m m Phe in vivo when simultaneously present in concentrations of 10 m m or higher.”

“ Phenylalanine uptake by T. crassiceps larvae is inhibited in a completely competitive fashion by serine , leucine, alanine, methionine, histidine, phenylalanine, tyrosine and tryptophan (in order of increasing affinity).”

“Replacement of Ala294 by either glycine or serine , thereby increasing or decreasing the size of the binding pocket, respectively, reduces affinity for phenylalanine.”