Species N Normalized curves Normalized curves + matching of derivative peaks Visual matching of derivative plots Matching of RAPD fingerprints Candida albicans 44 63.6 72.7 100 100 Candida glabrata 41 58.5 82.9 97.6 97.6 Candida krusei 39 64.1 82.1 97.4 100 Candida tropicalis 40 100.0 97.5 100 100 Saccharomyces cerevisiae 39 89.7
92.3 100 100 Candida parapsilosis 38 73.7 78.9 100 100 Candida lusitaniae 41 97.6 97.6 100 100 Candida guilliermondii 19 94.7 94.7 94.7 94.7 Candida pelliculosa 17 88.2 82.4 82.4-88.2 100 Candida metapsilosis 4 75.0 100.0 100 100 All species Ro 61-8048 concentration studied 322 79.5 86.7 98.1-98.4 99.4 Normalized curves column stays for accurate identification rate achieved when identification was based on automated www.selleckchem.com/products/psi-7977-gs-7977.html determination of the numerically closest match of the examined curve with known strain. Normalized curve + matching of derivative peaks column stays for the same amended by checking for decisive peaks in derivative plot. Visual matching of derivative plots column stays for accurate identification rate achieved when identification Belnacasan was based on simple visual comparison of examined derivative plot with plots of known strains. Accurate identification rate achieved upon evaluation and
matching of RAPD fingerprints is shown for reference in the last column. See Results and discussion for details. Since the peaks observed in a first derivative plot may in some cases represent the overall characteristic shape of a melting curve better, we also tested performance of matching peaks positions for identification purposes as the second possible approach. However, identification of individual melting peaks in a derivative plot and comparison of these results to those characteristic for each species cannot be automated as easily. Therefore, we first evaluated the presence of individual peaks in each species and each genotype. To reduce the amount of processed data and to identify typical positions of peaks in derivative curves, average first derivative curves were either first calculated for each species/genotype based on individual derivation
values of each strain of the respective species/genotype. Average curves are summarized in additional file 3: Average derivative curves. To establish the relevance of each averaged peak for species/genotype identification, these were subsequently classified into three categories: (i) decisive which occurred in all strains of the respective species/genotype, (ii) characteristic which occurred in 75-99% of strains of the respective species/genotype, and (iii) possible which occurred in less than 75% of strains. Presence of peaks in individual species/genotypes as described above is summarized in Table 3. Unfortunately, when we tested the reading of peaks positioning alone for yeast identification, unequivocal match was impossible in many cases (data not shown). Table 3 Average melting temperatures of peaks in first derivative plots obtained in individual species/genotypes.