start-ver=1.4 cd-journal=joma no-vol=1808 cd-vols= no-issue=1 article-no= start-page=490 end-page=497 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=201101 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Comparative study of the membrane-permeabilizing activities of mastoparans and related histamine-releasing agents in bacteria, erythrocytes, and mast cells en-subtitle= kn-subtitle= en-abstract= kn-abstract=The membrane-permeabilizing activities of mastoparans and related histamine-releasing agents were compared through measurements of K(+) efflux from bacteria, erythrocytes, and mast cells. Changes in bacterial cell viability, hemolysis, and histamine release, as well as in the shape of erythrocytes were also investigated. The compounds tested were mastoparans (HR1, a mastoparan from Polistes jadwagae, and a mastoparan from Vespula lewisii), granuliberin R, mast cell-degranulating peptide, and compound 48/80, as well as antimicrobial peptides, such as magainin I, magainin II, gramicidin S. and melittin. We used a K(+)-selective electrode to determine changes in the permeability to K(+) of the cytoplasmic membranes of cells. Consistent with the surface of mast cells becoming negatively charged during histamine release, due to the translocation of phosphatidylserine to the outer leaflet of the cytoplasmic membrane, histamine-releasing agents induced K(+) efflux from mast cells, dependent on their ability to increase the permeability of bacterial cytoplasmic membranes rich in negatively charged phospholipids. The present results demonstrated that amphiphilic peptides, possessing both histamine-releasing and antimicrobial capabilities, induced the permeabilization of the cytoplasmic membranes of not only bacteria but mast cells. Mastoparans increased the permeability of membranes in human erythrocytes at higher concentrations, and changed the normal discoid shape to a crenated form. The structural requirement for making the crenated form was determined using compound 48/80 and its constituents (monomer, dimer, and trimer), changing systematically the number of cationic charges of the molecules. en-copyright= kn-copyright= en-aut-name=NakaoSatoshi en-aut-sei=Nakao en-aut-mei=Satoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KomagoeKeiko en-aut-sei=Komagoe en-aut-mei=Keiko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=InoueTsuyoshi en-aut-sei=Inoue en-aut-mei=Tsuyoshi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KatsuTakashi en-aut-sei=Katsu en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University affil-num=2 en-affil= kn-affil=Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University affil-num=3 en-affil= kn-affil=Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University affil-num=4 en-affil= kn-affil=Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University en-keyword=Mastoparan kn-keyword=Mastoparan en-keyword=Compound 48/80 kn-keyword=Compound 48/80 en-keyword=Antimicrobial peptide kn-keyword=Antimicrobial peptide en-keyword=Histamine-releasing agent kn-keyword=Histamine-releasing agent en-keyword=Membrane permeability kn-keyword=Membrane permeability en-keyword=Cell shape kn-keyword=Cell shape END