To determine the relationship among the three-dimensional structures of PNLs and the lifestyle of PNL-producing microorganisms, we performed a phylogenetic analysis using protein sequences and deduced amino acid sequences reported for PNLs. A comparative analysis of the three-dimensional structure of the Clpnl2 protein predicted by homology modeling, covering the main body of the protein and the carbohydrate binding site, and the three-dimensional structures of the PNLs used in the phylogenetic analysis was also performed. Methods Strain and culture conditions C. lindemuthianum races 0 (non-pathogenic) and 1472 (pathogenic) were kindly provided by Dr. June Simpson (CINVESTAV-IPN, Unidad Irapuato, México) and maintained on potato

dextrose agar (PDA, Difco) at 20°C. For DNA extraction, mycelia from C. lindemuthianum race 1472 grown on potato dextrose (PD) for 9 click here days at 20°C with see more continuous shaking (150 rpm), was recovered by filtration through Whatman paper No. 1 and stored at -85°C. For

induction, 1.6 mg (about 5 cm2) of mycelia from races 0 and 1472 were inoculated in 250 ml-Erlenmeyer flasks containing 50 ml of PD medium and shaken (150 rpm) at 20°C. After 9 days, mycelia was collected by filtration, washed with water and transferred to 250 ml-Erlenmeyer flasks containing 50 ml of modified Mathur’s medium (10 mM MgSO4.7H2O, 20 mM KH2PO4, 36 mM L-glutamic acid, distilled water up to 1 L; final pH, 5.5) [35] supplemented with either 2.5% glucose, 92%-esterified pectin or cell walls from P. vulgaris. Flasks were shaken (150 rpm) at 20°C and after different periods of growth, mycelia was collected by filtration, washed with water and stored at -85°C until use. Preparation of plant cell walls Seedlings of P. dipyridamole vulgaris cv. Flor de Mayo were grown for 7 days, and cell walls were extracted and purified from hypocotyls as described elsewhere [36]. DNA and RNA isolation Genomic DNA was isolated from C. lindemuthianum mycelia that had been grown for 9 days in PD medium according to standard protocols [37]. Total RNA was purified from mycelia using TRIzol reagent (Invitrogen). RNA samples

were treated with DNAse I according to manufacturer’s this website instructions (Invitrogen) to eliminate DNA. The quality and concentration of total RNA were verified using the RNA 6000 Nano LabChip kit (2100 Agilent Bioanalyzer). Isolation of the homologous DNA Clpnl2 probe from C. lindemuthianum Genomic DNA from race 1472 was amplified by PCR using the upstream primer pnlD (5′-CAGTACGTCTGGGGTGGTGA-3′) and downstream primer pnlR (5′-AAGTAGTTGTTGACGACGTGG-3′, which are homologous to sequences between 595 and 614 nt and 891 and 911 nt, respectively, of exon 3 of the Clpnl2 gene from C. gloeosporioides [GenBank: AAD43565]. The PCR incubation mixture was heated at 95°C for 5 min in a thermocycler (Eppendorf Master Cycler Gradient, Brinkmann, Westbury, NY), followed by denaturation for 1 min at 95°C, annealing for 2 min at 48°C and extension for 2 min at 72°C.