Draft genome sequence of Escherichia coli M51-3: a multidrug-resistant strain assigned as ST131-H30 recovered from infant diarrheal infection in Mexico.

OBJECTIVES: In this study, we report the draft genome sequence of a multidrug-resistant (MDR)Escherichia coli strain recovered from stool sample of an outpatient infant girl with acute diarrheal infection in Mexico. METHODS: Antimicrobial susceptibility testing and PCR-based detection of diarrheagenic E. coli (DEC) were performed. In addition, genomic DNA from E. coli strain M51-3 was sequenced using Ion Torrent PGM platform with 200-bp chemistry and generated reads were de novo assembled using SPAdes v3.11. The draft genome was annotated and analyzed regarding multilocus sequence typing (MLST), serotyping, fimH typing, plasmid replicons, acquired antimicrobial resistance and virulence genes using web tools available at the Center for Genomic Epidemiology. RESULTS: A draft genome comprising 5 088 545 bp in length and 5308 protein-coding sequences was generated. In silico typification revealed that E. coli strain M51-3 belongs to ST131-O25:H4-H30 pandemic subclone. Several genes associated with resistance to ß-lactams [blaTEM-1B], aminoglycosides [aph(3'')-Ib, aadA5, aph(6)-Id and aac(3)-IId], sulfonamides [sul1 and sul2], trimethoprim [dfrA17], and tetracycline [tet(A)] were identified. Besides, point mutations in gyrA, parC, and parE genes were detected. Interestingly, the enterotoxin-coding virulence gene senB was evidenced. CONCLUSIONS: To our knowledge, this is the first draft genome of an E. coli ST131-O25:H4-H30 strain recovered from infant diarrheal stool sample in Mexico. The genome sequence of E. coli M51-3 presented here will be helpful to understand the genomic diversity of this highly virulent and MDR successfully pandemic bacterial pathogen.

Fungal spore concentrations in indoor and outdoor air in university libraries, and their variations in response to changes in meteorological variables.

The fungal spore concentration (FSC) in the air poses a risk for human health. This work studied the FSC in university libraries and how it is affected by environmental factors. A total of 347 samples were obtained using a Microbio MB2(®) Aerosol Sampler. The wind speed (WS), cross wind (CW), temperature (T), relative humidity (HR), barometric pressure (BP) and dew point (DP) were recorded using a Kestrel(®) 4500 weather station. The median indoor/outdoor FSC was 360/1230 CFU m(-3). FSC correlated inversely with BP, HR and DP; and positively with WS and CW; whereas T showed negative or positive correlation with FSC, depending on the region or sampling time. Eleven fungal genera were found and the dominant isolates were identified as Aspergillus niger, Aspergillus tamarii and Aspergillus oryzae. All fungi identified are known to be allergenic. It was concluded that environmental variables can influence the air FSC in different ways.