Table 1.
Statistic analyses of melting temperature (Tm) values obtained in the dissociation curve after qPCR using DNA purified from cultivated strain and purified from cerebrospinal fluid (CSF) sample.
Fig 1.
Mean of the Melting Temperature (Tm) values for all replicates for each DNA extracted from strain or CSF sample by silica column or by heating.
Each column represents the data obtained for one gene which is identified at the top. Short horizontal bars indicate the mean; Vertical bars show the standard deviation; Long horizontal bars represent the significance of differences calculated by the Tukey’s Multiple Comparison Test and shown by asterisks: **P < 0.01 and ***P < 0.001. For the mef gene, it was calculated by unpaired t-test: ns means not significant (P > 0.05).
Table 2.
Antimicrobial sensitivity profile and genotypes of clinical isolates using SYBR Green qPCR multiplex.
Fig 2.
Fluorescence melting peaks obtained by plotting the negative derivative of fluorescence over temperature (-dF/dT) versus temperature (T) in the SYBR Green channel (465–510 nm) for the SYBR Green qPCR multiplex.
Each gene combination observed in this study is represented here: Combination 1—susceptible to three classes of antibiotics, only pbp2b gene was positive; 2—susceptible to penicillin and resistant to clindamycin and erythromycin, pbp2b and ermB genes were positive; 3—resistant to penicillin and susceptible to clindamycin and erythromycin, all three genes were negative; 4—resistant to three classes of antibiotics, with multiples mechanisms of resistance, pbp2b was negative, ermB and mef genes were positive; 5—resistant to penicillin, clindamycin and erythromycin, ermB gene was positive. The peaks were identified with the name of the genes that they represent.
Fig 3.
Genetic profile of resistance genes detected in all strains or CSF samples received from 2014 to 2020: A—Distribution in percent of all 86 samples per genotype; B—Distribution in percent per year of all 86 samples.
The total of results per genotype is indicated inside of each bar; Genotypes: P+E-M- means pbp2b positive, ermB and mef negative; P+E+M- means pbp2b and ermB positive and mef negative; P-E-M- means pbp2b, ermB and mef negative; P-E+M+ means pbp2b negative, ermB and mef positive; P-E+M- means pbp2b and mef negative, and ermB positive; P-E-M+ means pbp2b and ermB negative, and mef positive; P+E-M+ means pbp2b and mef positive, and ermB negative.