Genome structure and novel mutations in quinolone resistance-determining region genes of Ureaplasma spp.

2016 Fiscal Year Final Research Report

• Project/Area Number: 26870923
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Infectious disease medicine; Bacteriology (including mycology)
• Research Institution: Research Institute, Osaka Medical Center for Maternal and Child Health
• Principal Investigator: KAWAI YASUHIRO 地方独立行政法人大阪府立病院機構大阪府立母子保健総合医療センター(研究所), 免疫部門, 客員研究員 (10388936)
• Co-Investigator(Renkei-kenkyūsha): YANAGIHARA Itaru 大阪母子医療センター研究所, 免疫部門, 部長 (60314415)
• Research Collaborator: NAKURA Yukiko 大阪母子医療センター研究所, 免疫部門, 研究補助員
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: ウレアプラズマ / 全ゲノム解析 / 薬剤感受性 / キノロン耐性決定領域

Outline of Final Research Achievements

Ureaplasma spp. cause several disorders, such as preterm delivery with lung infections in neonates. They are opportunistic pathogens that commonly inhabit the human urogenital tract; they lack a peptidoglycan layer and hydrolyze urea. The complete genome sequence of Ureaplasma parvum serovar 3, clinical strain SV3F4 isolated from a Japanese patient with a history of an infectious abortion, included a 727,289-bp contig with a G plus C content of 25.55%.
Out of 28 clinical Ureaplasma strains, we isolated 9 with high MICs of quinolones and found a single parC gene mutation, resulting in the change S83L. Novel mutations of ureaplasmal ParC (S83W and S84P) were independently found in one of the samples. Homology modeling of the ParC S83W mutant suggested steric hindrance of the quinolone-binding pocket (QBP), and de novo prediction of peptide structures revealed that the ParC S84P may break/kink the formation of the alpha 4 helix in the QBP.

Free Research Field

感染症学、小児科学、微生物学、分子生物学