| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1387-1 | ||||
Resumo:Microbial contamination is one of the main risks associated with drug production. The precise identification of the microbiota detected in the pharmaceutical production environment is essential for investigating sources of contamination, and for carrying out preventive and corrective actions. Studies using the Matrix-Assisted Laser Desorption Ionization-Time of Flight/Mass Spectrometry (MALDI-TOF/MS) methodology, which provides information about the bacterial proteome, have shown good rates in the identification of strains of pharmaceutical origin compared to other phenotypic methodologies, in addition to the high speed in obtaining results. The aim of this study was to compare two MALDI-TOF MS systems for the identification of bacterial strains isolated from an immunobiological manufacturing facility, not previously identified by the semi-automated system VITEK®2. Forty six strains isolated from 2015 to 2019 were analyzed using the MALDI Biotyper® (Bruker) and VITEK® MS (bioMérieux) systems, according to the manufacturers' instructions, and by the programs Biotyper®2.0 (Bruker Daltronics, Bremen, Germany) and Saramis Premium (version 4.0.0.14), respectively. The identification was confirmed through the complete sequencing of the 16S rRNA gene using the MicroSEQ® Full Gene 16S rDNA kit and using the EZBioCloud database. Strains with similarity > 98.7% compared to the sequences present in the database were considered possible species. Of the 46 strains analyzed by the VITEK® MS system, 42 (91.3%) weren`t identified and four (8.7%) were identified at the genus level. The 16S rRNA gene sequencing analysis confirmed the genus of the four (100.0%) strains. The MALDI Biotyper® system was able to identify 16 (34.8%) strains, 10 (62.5%) at the genus level and six (37.5%) at the species level. Among the strains identified at the genus level, seven (70.0%) genera were confirmed by 16S rRNA sequencing; two were identified by the basonym of Sutcliffiella cohnii (Bacillus cohnii) by MALDI Biotyper®; and one was identified as Bacillus siralis by MALDI Biotyper® and Microbacterium laevaniformans by sequencing. Of the six strains identified at the species level by MALDI Biotyper®, four (66.6%) species were confirmed by sequencing, and two others were among the possible species showed by EzBioCloud with similarity above 98.7%. In conclusion, the MALDI-TOF/MS system was unable to identify most of the strains evaluated. However, MALDI Biotyper® showed higher identification efficiency than VITEK® MS, suggesting that the database of the former presents a greater number of spectra of bacteria species from the pharmaceutical environment. The database customization, based on the introduction of new spectra of environmental strains, becomes a good alternative for improving the MALDI-TOF/MS ability to obtain better identification results. Palavras-chave: Bacterial identification, pharmaceutical industry, MALDI-TOF/MS | |||||