백색부후균인 느타리버섯 60균주로부터 목재를 분해하는 리그닌-셀룰로오스 분해효소 생산 능력이 우수한 균주를 선발하였다. 그 결과 1, 2차 스크리닝을 통해 실험한 모든 균주에서 리그닌-셀룰로오스 분해효소를 생산하는 것을 확인하였다. 그러나, 아비셀 함유 평판배지에서 선발된 6개 균주의 경우 2차 스크리닝 아비셀-효모추출물-펩톤 액체배지에서 셀룰로오스 분해효소 활성이 낮은 것을 확인하였다. 자일란 분해효소의 경우 자일란-효모추출물-펩톤 액체배지에서 No. 6, No. 38균주에서 xylanse 1.0 U/ml 이상, 1,4-β-xylosidase 0.15 U/ml 이상 생산되었다. RBBR 함유 평판배지에서 선발된 13개 균주를 가지고 글루코오즈-효모-펩톤 배지 조건하에서 리그닌 분해 효소의 생산 실험을 한 결과 락케이즈가 먼저 최대 활성(0.8~2.0U/ml)을 나타낸 뒤 Mn-dependent peroxidase가 최대활성(0.5~1.5U/ml)를 나타내었다. 한편, 글루코오즈-효모-펩톤 배지 조건하에서 실험한 모든 균주에서 lignin peroxidase는 생산되지 않았다. 특히 본 연구자는 이러한 스크리닝 방법에 의해 Mn-dependent peroxidase와 laccase 생산 능력이 높은 No. 42균주를 선발하였다.

Ceriporiopsis subvermispora is a unique white rot fungus degrading plant cell wall lignin without severe loss of cellulose. Recombinant plasmids containing homologous gene expression signals fused to the coding sequence of Escherichia coli hph which encodes for hygromycin phosphotransferase were introduced in protoplasts of wild type C. subvermispora using PEG/CaCl2 protocol. A number of hygromycin B resistant strains were isolated on a screening plate containing 100㎍/ml of hygromycin B: whereas, no colonies were observed when protoplasts were treated with no DNA as a negative control. It was demonstrated that most of the isolates lost their drug resistance during successive cultivations in the presence of the same concentration of hygromycin B, but some of the isolates showed stable drug resistance after five times repeated screening. They did not lose the drug resistance even after the cultivation in the absence of hygromycin B and incorporation of the hph sequence was confirmed by specific amplification of the target sequence in PCR experiments and Southern hybridization analysis. The stable transformation system will make it possible to do molecular genetic analysis, as well as breeding of genetically modified strains, in C. subvermispora. Moreover, it was demonstrated that recombinant constructs with truncated promoter showed reduced number of the drug resistant isolates on the first screening plate, in response with the length of the remaining promoter sequence. These findings indicated that unstable drug resistance observed in these isolates should originate from transient expression of the introducing marker genes, and that a promoter assay system has been developed for the first time in basidiomycete. This system is practically not affected by the positional effect of the integrated recombinant gene in the host chromosome.

Basidiomycetes can degrade lignocellulosic biomass, and some basidiomycetes produce alcohol dehydrogenase, so it is feasible to produce alcohol from basidiomycetes. Agaricus blazei, Flammulina velutipes and Tricholoma matsutake have been used for mushroom fermentation to produce alcohol. To investigate whether Pholilta nameko can be used for mushroom fermentation, and find out the relationship between mannitol-1-phosphate dehydrogenase and alcohol dehydrogenase, we cloned mannitol-1-phosphate dehydrogenase gene from P. nameko, which is a zinc-containing long- chain alcohol dehydrogenase. Mpd, the gene encoding mannitol-1-phosphate dehydrogenase (MPD), has been sequenced and characterized from basiodiomycete P. nameko. The length of the coding region is 1360bp. The gene encodes a putative protein of 359 amino acids; predicted protein molecular weight is 38.6 kDa and an isoelectric point is PI = 7.34. The locations of exons and introns in the gene were deduced on the basis of interruptions in the amino acid sequence that were homologous to those in the MPD of Laccaria bicolor, the coding region was split into 6 exons and 5 introns. The protein deduced from the gene MPD showed more than 46% sequence identity to 20 fungal MPDs or alcohol dehydrogenases documented in the Gene bank protein database, based on BLASTP analysis, and was phylogenetically close to the MPDs of L. bicolor and Coprinopsis cinerea. This protein shared the same conserved domain with the alcohol dehydrogenase.

리퀴리티게닌과 이소리퀴리티게닌은 감초의 주요 플라보노이드 성분이다. 이들 플라보노이드는 수용성 감초추출물과 β-glucosidase를 생성하는 잎새버섯 HB0071 균사체 발효배양을 통하여 생산하였다. 감초추출물 내 리퀴리티게닌과 이소리퀴리티게닌은 잎새버섯 발효배양 동안 현저히 증가하였다. 이 균주의 β-glucosidase의 활성은 배양 96시간을 기준으로 최고 91.5 mU/mL로 확인되었으며, 감초추출발효물로부터 생성된 리퀴리티게닌과 이소리퀴리티게닌의 함량은 HPLC 분석을 통하여 최대 568.5 μg/mL과 89.6 μg/mL로 확인되었다. 본 연구에서는 감초추출물의 잎새버섯 발효 전․후의 시료가 처리된 각질형성세포를 이용하여 자외선 UVB에 조사로 발현된 염증유발인자(COX-2)와 사이토카인(IL-1β, IL-6) 모두 감초추출발효물(FLEx)에서 농도의존적으로 발현이 억제되는 것을 확인하였다. 결론적으로 리퀴리티게닌과 이소리퀴리티게닌의 함량이 증가된 감초추출발효물은 자외선으로부터 손상된 피부 염증반응을 완화시켜줄 것으로 사료된다.