title: Evaluating the antibacterial property of gold-coated hydroxyapatite: a molecular biological approach.
abstract: Hydroxyapatite nanoparticles (HAP NPs) are one of the widely used biocompatible materials. However, information about the reaction between HAP NPs and microorganisms is insufficient. This paper aims to understand the antibacterial property of a new nanocomposite consisting of gold-coated HAP and alginate polymer (namely, Au-HAP@Alg NPs). To the best of our knowledge, we reported the first information regarding to MIC (25mg/mL), DIZ (no visible zone), and IC50 (0.5mg/mL) of Au-HAP@Alg NPs toward the microorganism Escherichia coli TOP10. The real-time gene expression levels of polA, polB, cyd, mdoG, GAPDH, and 16S rRNA were maintained at stable levels up until conditions of 2.5mg/mL Au-HAP@Alg NPs. The results showed that 16S rRNA can be a good reference under these conditions. The expressions of GAPDH, cyd, and mdoG were inhibited obviously under condition of 10mg/mL of Au-HAP@Alg NPs. Our results indicated that the possible antibacterial mechanism of Au-HAP@Alg was through the interaction with these carbohydrate and cell wall-related genes. This novel biocompatible and antibacterial material can potentially be applied in medical and environmental fields.
authors.affiliation: Department of Bioenvironmental Engineering and Research Center for Analysis and Identification, Chung Yuan Christian University, No. 200, Chung-Pei Road, Jhong-Li 32023, Taiwan; Center for Biomedical Technology (CBT), Chung Yuan Christian University, No. 200, Chung-Pei Road, Jhong-Li 32023, Taiwan. Electronic address: yt_huang@cycu.edu.tw.
authors.forename: Yu-Tzu
authors.initials: YT
authors.lastname: Huang
authors.affiliation: World Premier International Research Center for Materials Nanoarchitectonics, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan; Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo 169-8555, Japan; PRESTO, Japan Science and Technology Agency (JST), 4-1-8, Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Yamauchi
authors.affiliation: Department of Bioenvironmental Engineering and Research Center for Analysis and Identification, Chung Yuan Christian University, No. 200, Chung-Pei Road, Jhong-Li 32023, Taiwan.
authors.forename: Chung-Wei
authors.initials: CW
authors.lastname: Lai
authors.affiliation: Department of Bioenvironmental Engineering and Research Center for Analysis and Identification, Chung Yuan Christian University, No. 200, Chung-Pei Road, Jhong-Li 32023, Taiwan.
authors.forename: Wei-Jung
authors.initials: WJ
authors.lastname: Chen
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics; D005798:Genes, Bacterial / Q000187:drug effects; D006046:Gold / Q000737:chemistry*; D006882:Hydroxyapatites / Q000737:chemistry / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D008826:Microbial Sensitivity Tests; D053761:Nanocomposites / Q000737:chemistry*; D010957:Plasmids; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D059467:Transcriptome / Q000187:drug effects
chemical_list: D000464:Alginates; D000900:Anti-Bacterial Agents; D006882:Hydroxyapatites; D012336:RNA, Ribosomal, 16S; D006046:Gold
keywords: Bactericidal activity; Gene expression; Gold; Hydroxyapatite; QPCR