The extrolites were identified by their retention times and UV spectra. Authentic analytical standards were employed for PF-02341066 molecular weight retention time and retention index comparison with the extrolites detected. Results Phylogenetic analysis The ITS regions and parts of the β-tubulin and calmodulin gene were sequenced and analysed. The trees obtained from the maximum parsimony analysis are shown in Figs. 1, 2, 3. Molecular data revealed that six species are related to P. citrinum. Four of these species are strictly anamorphic, P. hetheringtonii, P. sizovae, P. steckii and P. gorlenkoanum, and two form a teleomorph, namely P. tropicum

and P. tropicoides. Fig. 1 One of the 128 equally most parsimonious trees of the analysed ITS region (55 of the 629 characters were parsimony informative; tree length = 95, CI = 0.652, RI = 0.948, RC = 0.653) Fig. 2 One of the two equally most parsimonious trees of the analysed BenA region (71 of the 473 characters were parsimony informative; tree length = 166, CI = 0.898, RI = 0.964, RC = 0.865) Fig. 3 One of the six equally most parsimonious trees Ivacaftor chemical structure of the analysed Cmd region (89 of the 456 characters were parsimony informative; tree length = 171, CI = 0.872, RI = 0.959, RC = 0.836) The ITS

regions included 520 bp, of which 10% were parsimony-informative. The heuristic search generated more than 5,000 equally parsimonious trees, which were 129 steps long. Phylogenetic analysis of the ITS dataset resulted in low bootstrap supports of the clades and only the connection between P. citrinum and P. hetheringtonii was highly supported (100%). Both P. sumatrense and P. gorlenkoanum were basal to P. citrinum and related species. However, this is not supported by the β-tubulin and calmodulin datasets. Penicillium gorlenkoanum appeared to be related to RAS p21 protein activator 1 P. citrinum in these datasets, and P. sumatrense formed a

clade unrelated to P. citrinum, P. westlingii, P. paxilli, P. roseopurpureum or P. shearii (data not shown). A gap of 36–38 bp was observed in the ITS1 region of all P. citrinum and P. hetheringtonii isolates. However, analysis of other Penicillium strains showed that this feature is not species specific, since one isolate of P. manginii (CBS 327.79) also has this deletion, while another has not (CBS 253.31T). The ITS dataset showed less resolution than the β-tubulin and calmodulin datasets, and P. tropicum and P. tropicoides had no differences in their ITS regions. The other five species could be differentiated based on their ITS sequence, and a subgroup in the P. steckii clade was observed. This subgroup, characterized by a single basepair difference on position 164 of the ITS2 region, included the type strain of P. corylophiloides nom. inval. (CBS 325.59). The β-tubulin and calmodulin datasets were more variable than the ITS dataset. The β-tubulin dataset consisted of 473 bp, of which 15% was parsimony informative.