Cloning and expression of cellulase gene of cbh-1 and egl-1 and molecular systematics of Ganoderma

• Main Authors: I-Cheng Ho, 何一正
• Other Authors: Johannes Scheng-Ming Tschen
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/05647294246892304690

博士 === 國立中興大學 === 植物學系 === 88 === One group of white rot fungus, Ganoderma spp., is very difficult to be identified by traditional taxonomic characters. We collected 24 isolates of Ganoderma spp. from Guandaushi forest. Based on morphological characteristics, 12 isolates were grouped to Ganoderma, 9 isolates to Elfvingia, and 3 isolates to Amauroderma. Three species were identified as G. lucidum, G. sinense, G. tropicum and three new records in Taiwan were G. lobatum, G. tornatum, G. kumingnese. Based on ITS1 and ITS2 DNA sequences database of Ganoderma spp., we construct evolution model by using kimura''s two-parameter method to caculate the divergence of DNA sequence, and Fitch-Margoliash method to search the evolution tree, then compare with the results of parsimony method. The results indicated that the Ganoderma spp. could be divided into two major group, Ganoderma group (which was classfied into 8 groups) and Elfvingia group (which was classfied into 11 groups). The central species of this evolution model is Ganoderma lucidum complex, which was proposed to be the ancestor species by the shortest evolution distance. This model also suggested some synonymy, which including 1. G. formosanum, G. janponicum and G. sinense. 2. G. microsporum and G. weberianum 3. G. sessile, G. zonatum and G. platense. 5. G. resinaceum and G. pfeifferi. The close related groups include 1. G. weberianum, G. capense and G. neo-japancum, 2. G. fomicatum and G. tropicum 3. G. australe and G. gibbosum. Because of the morphogical similarity of the group members in this model, DNA evolution was related with the morphologic characteristics. Twenty-four types of ITS1 sequences of Ganoderma spp. were selected for standard molecular typing. Five isolates were recognized as G. tornatum, G. sinense, G. lucidum, G. tsugae and G. tropicum. Ten isolates of Ganoderma sp. were positive on cellulose degration activity test and cbh1 gene, about 800 bp in length, could be detected by PCR. Employing NCBI Blastx software, the putative amino acid sequence of cbh1 gene of Ganoderma sp. G419 shows similarity with Iprex lacetus CBHI (73 %) and Phanerochaete chrysoporium (75 %). The cDNA library of Ganoderma sp. G419 were screening for CMCase enzyme activity. Two kinds of proteins from 10 clones with CMCase activity were detected as 40 kDa and 70 kDa.