Peptide Flexibility and the Hydrophobic Moment are Determinants to Evaluate the Clinical Potential of Magainins

Non-canonical helical transitions and conformational switching are associated with characteristic flexibility and disorder indices in TRP and Kv channels

“…Basically, our FlexiProt algorithm predicts the local side-chain flexibility, which correlates the composition of amino acids in a protein sequence in the context of the N - and C-terminal neighbors for each residue coded in the primary sequence. The program assigns a weighted normalized B-factor value based on a stiffness classification, according to structural aspects associated with the theoretical degrees of freedom for each of the 20 side-chains [ 25 , 26 ]. Thus, normalized B-factors are clear indication of the local residue flexibility according to the next expression:…”

Physical–Chemical Approach to Designing Drugs with Multiple Targets

“…It is known that the peptides based on magainin-2 were found to be more flexible when the amino acid arginine (R) was at position 10 in the sequence than when tryptophan (W) was at the same position. 53 It was argued that this is due to the arginine allowing for kinking, while tryptophan made the peptide stiffer and less flexible. The flexibility of AMPs might also be important for their antiviral functioning, because it could allow them to associate with a larger number of protein receptors, blocking viruses from associating with them.…”

“…The larger fraction of R residues could also be associated with the greater flexibility of antiviral peptides. It is known that the peptides based on magainin-2 were found to be more flexible when the amino acid arginine (R) was at position 10 in the sequence than when tryptophan (W) was at the same position . It was argued that this is due to the arginine allowing for kinking, while tryptophan made the peptide stiffer and less flexible.…”

From a hunger-regulating hormone to an antimicrobial peptide: gastrointestinal derived circulating endocrine hormone-peptide YY exerts exocrine antimicrobial effects against selective gut microbiota

“…Intriguingly, PYY 1–36 shares structural similarities with magainin 2, an antimicrobial peptide recognized for its protective function against bacterial and fungal infections in the skin of African clawed frogs. 7 , 8 This structural resemblance has attracted further research into the potential inhibitory effect of PYY on the growth and viability of C. albicans , the predominant fungus residing in the human gut. C. albicans which reside as a commensal yeast in the intestinal tract can transition into a pathogenic hyphal form under specific conditions (e.g., exposing mucins).…”