Laboratory of Microbiological Control, Bio-Manguinhos/Fiocruz, CEP 21040-900, Rio de Janeiro, Brazil.
Laboratory of Microbiology of Food and Sanitizes, INCQS/Fiocruz, CEP 21040-900, Rio de Janeiro, Brazil.
J Appl Microbiol. 2023 Oct 4;134(10). doi: 10.1093/jambio/lxad236.
Evaluate methods for identification and typing of Stenotrophomonas maltophilia isolated from a pharmaceutical facility.
From 270 S. maltophilia strains identified by VITEK®2, 40 were selected and submitted to MALDI TOF-MS, 16S and 23S rRNA gene analysis, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and an antimicrobial susceptibility profile. 16S rRNA sequencing was able to identify 39 (97.5%) strains as Stenotrophomonas spp. and one (2.5%) as Luteimonas huabeiensis. MALDI TOF-MS identified 37 (92.5%) strains as S. maltophilia, and three (7.5%) were not identified. PCR targeting 23S rRNA yielded a positive result for 39 (97.5%) strains. However, after sequencing, two strains were identified as Stenotrophomonas rhizophila, showing false-positive results. The confirmed S. maltophilia strains (n = 37) showed 35 distinct ERIC-PCR profiles and exhibited sensitivity to minocycline and levofloxacin, and six (16.3%) showed intermediate resistance to sulfamethoxazole-trimethoprim.
Matrix-assisted laser desorption lonization-time of flight mass spectrometry (MALDI-TOF MS) was a satisfactory methodology for the identification of S. maltophilia, but expansion of the database is necessary for the identification of other species. 16S rDNA sequencing showed low resolution for Stenotrophomonas species differentiation. PCR targeting 23S rRNA could not differentiate S. maltophilia from S. rhizophila. ERIC-PCR was shown to be a useful tool for the microbial source tracking of S. maltophilia.
评估从制药厂分离出的嗜麦芽寡养单胞菌的鉴定和分型方法。
从 VITEK®2 鉴定的 270 株嗜麦芽寡养单胞菌中，选择 40 株进行 MALDI-TOF-MS、16S 和 23S rRNA 基因分析、肠杆菌重复基因间一致性聚合酶链反应（ERIC-PCR）和抗菌药物敏感性分析。16S rRNA 测序可鉴定 39 株（97.5%）为嗜麦芽寡养单胞菌，1 株（2.5%）为华北黄单胞菌。MALDI-TOF-MS 鉴定出 37 株（92.5%）为嗜麦芽寡养单胞菌，3 株（7.5%）未鉴定出。针对 23S rRNA 的 PCR 检测 39 株（97.5%）呈阳性。然而，测序后发现 2 株为嗜粘质沙雷氏菌，出现假阳性结果。经确认的嗜麦芽寡养单胞菌（n=37）表现出 35 种不同的 ERIC-PCR 图谱，对米诺环素和左氧氟沙星敏感，6 株（16.3%）对磺胺甲噁唑-甲氧苄啶表现为中介耐药。
基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）是鉴定嗜麦芽寡养单胞菌的一种满意方法，但需要扩展数据库以鉴定其他物种。16S rDNA 测序对嗜麦芽寡养单胞菌种的区分分辨率较低。针对 23S rRNA 的 PCR 无法区分嗜麦芽寡养单胞菌和嗜粘质沙雷氏菌。ERIC-PCR 被证明是追踪嗜麦芽寡养单胞菌来源的有用工具。
