Denatured bactericidal proteins: Active per se, or reservoirs of active peptides?

• Published in: FEBS letters 2011-08, Vol.585 (15), p.2403-2404
• Main Author: D’Alessio, Giuseppe
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Antimicrobial Cationic Peptides - immunology; Bacteria; Bactericidal activity; Blood Bactericidal Activity - immunology; Destructured proteins; Humans; Peptide Fragments - immunology; Peptides; Protein Denaturation; Proteins - chemistry; Proteins - immunology; Structure-to-function paradigm
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/j.febslet.2011.07.009

► Bactericidal proteins loose their various activities when they are denatured or inactivated, but remain bactericidal. ► The hypothesis is that these proteins are not bactericidal per se, but are merely containers of bactericidal peptides. According to the structure-to-function paradigm proteins fold into a 3D structure for exerting their functions. Intrinsically destructured proteins with important biological functions have been identified and studied, but they assume a structure when interacting in the cell with their partners. There are instead bactericidal proteins, endowed also with other diverse activities (glycoside hydrolases, RNases, a defensin), which are lost when the proteins are denatured or inactivated, whereas the bactericidal activity is surprisingly conserved. The hypothesis is advanced that these proteins are not bactericidal per se, but because they store in their amino acid sequences peptide segments that display bactericidal activity when cut out as free peptides from the proteins. These bactericidal proteins would thus be merely containers of bactericidal peptides.