Thumbnail
Access Restriction
Subscribed

Author Taniguchi, Masayuki ♦ Ochiai, Akihito ♦ Takahashi, Kiyoshi ♦ Nakamichi, Shun-Ichi ♦ Nomoto, Takafumi ♦ Saitoh, Eiichi ♦ Kato, Tetsuo ♦ Tanaka, Takaaki
Source World Health Organization (WHO)-Global Index Medicus
Content type Text
Publisher Elsevier
File Format HTM / HTML
Language English
Difficulty Level Medium
Subject Domain (in DDC) Technology ♦ Medicine & health ♦ Chemical engineering
Subject Keyword Discipline Biomedical Engineering ♦ Discipline Microbiology
Abstract The antimicrobial peptide AmyI-1-18 is a cationic -helical octadecapeptide derived from -amylase in rice (Oryza sativa L. japonica) that contains four cationic amino acid residues (two arginines and two lysines). To enhance the antibacterial activity of AmyI-1-18 against Porphyromonas gingivalis (a bacterium associated with periodontal disease), we synthesized 12 analogs bearing substitutions with alanine, leucine, and/or arginine that were designed based on helical wheel projections and investigated their antibacterial properties. The antibacterial properties of four analogs bearing substitution of a single arginine or lysine with alanine were almost similar to those of AmyI-1-18, suggesting that the antibacterial properties depend on the presence of three cationic amino acid residues. Of three single arginine-substituted analogs, AmyI-1-18(G12R) exhibited an antibacterial activity 2.8-fold higher [50% growth-inhibitory concentration (IC ): 4.6 µM] than that of AmyI-1-18 (IC : 13 µM). Likewise, the antibacterial properties of two single leucine-substituted analogs were significantly enhanced; in particular, AmyI-1-18(N3L) exhibited an antibacterial activity (IC : 2.5 µM) 5.2-fold higher than that of AmyI-1-18. The hemolytic activity of AmyI-1-18(N3L) against mammalian red blood cells was low (2% at 50 µM). A membrane-depolarization assay using a membrane potential-sensitive fluorescent dye revealed that, similar to AmyI-1-18, the antibacterial activity of AmyI-1-18(N3L) was not dependent on its membrane-disrupting activity. Our results demonstrate that the antibacterial properties of AmyI-1-18 against P. gingivalis are significantly improved, without a significant increase in hemolytic activity, by replacing asparagine with leucine at position 3.
Description Author Affiliation: Taniguchi M ( Department of Materials Science and Technology, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan); Ochiai A ( Department of Materials Science and Technology, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.); Takahashi K ( Department of Materials Science and Technology, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.); Nakamichi SI ( Department of Materials Science and Technology, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.); Nomoto T ( Department of Materials Science and Technology, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.); Saitoh E ( Graduate School of Technology, Niigata Institute of Technology, Niigata 945-1195, Japan.); Kato T ( Department of Chemistry, Tokyo Dental College, Tokyo 101-0062, Japan.); Tanaka T ( Department of Materials Science and Technology, Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.)
ISSN 13891723
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Reading ♦ Research ♦ Self Learning
Interactivity Type Expositive
Education Level UG and PG
Learning Resource Type Article
Publisher Date 2016-12-01
Publisher Place Japan
e-ISSN 13474421
Journal Journal of Bioscience and Bioengineering
Volume Number 122
Issue Number 6


Source: WHO-Global Index Medicus