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The diversity of endophytic and saprobic fungi from Magnolia liliifera leaves were observed and analyzed to establish relationships. Nine endophytes were morphologically and phylogenetically similar to the saprobes; Colletotrichum gloeosporioides, Colletotrichum sp. 2, Corynespora cassiicola, Fusarium sp. 1, Guignardia mangiferae, Leptosphaeria sp., Phomopsis sp. 2, Phomopsis sp. 6, and Phomopsis sp. 10. The endophytes were found to produce the same degrading enzymes as their saprobic counterparts. The isoform of β-mannanase produced from each of endophyte and saprobe counterparts were similar. Fungal succession and enzyme production patterns during leaf decomposition were correlated. The occurrence of saprobes was found to be related to the enzymes that the fungi produce. The study provides further compelling evidence that endophytes can switch lifestyle to saprobes.

Enzymes from filamentous fungi are already widely exploited, but new applications for known enzymes and new enzymic activities continue to be found. In addition, enzymes from less amenable non-fungal sources require heterologous production and fungi are being used as the production hosts. In each case there is a need to improve production and to ensure quality of product. While conventional, mutagenesis-based, strain improvement methods will continue to be applied to enzyme production from filamentous fungi the application of recombinant DNA techniques is beginning to reveal important information on the molecular basis of fungal enzyme production and this knowledge is now being applied both in the laboratory and commercially. We review the current state of knowledge on the molecular basis of enzyme production by filamentous fungi. We focus on transcriptional and post-transcriptional regulation of protein production, the transit of proteins through the secretory pathway and the structure of the proteins produced including glycosylation.

One of the most economically-viable processes for the bioconversion of many types of lignocellulosic wastes is represented by edible mushroom cultivation. Lentinula edodes, Volvariella volvacea and Pleurotus sajor-caju are three important commercially cultivated mushrooms which exhibit varying abilities to utilise different lignocellulosics as growth substrate. Examination of the lignocellulolytic enzyme profiles of the three species show this diversity to be reflected in qualitative variations in the major enzymic determinants (i.e. cellulases, ligninases) required for substrate bioconversion. For example, L. edodes, which is cultivated on highly lignified substrates such as wood or sawdust, produces two extracellular enzymes which have been associated with lignin depolymerisation in other fungi, (manganese peroxidase and laccase). Conversely, V. volvacea, which prefers high cellulose-, low lignin-containing substrates produces a family of cellulolytic enzymes including at least five endoglucanases, five cellobiohydrolases and two β-glucosidases, but none of the recognised lignin-degrading enzymes.

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~~~The nematophagous fungus Verticillium chlamydosporium secreted several proteases in submerged culture in which soya peptone was the sole carbon and nitrogen source. One protease, VCPl (M, 33000, pl102), was purified 14-fold from culture filtrates to apparent homogeneity using preparative isoelectric focusing in free solution, and shown to rapidly hydrolyse the chymotrypsin substrate Suc-(Ala),-Pro-Phe-pNA and elastin. VCPl had a Km for Suc-(Ala),-Pro-Phe-pNA of 4 3 x to PMSF and TPCK, but only moderately sensitive to chicken egg-white and soya bean trypsin inhibitors. VCPl degraded a wide range of polymeric substrates, including Azocoll, hide protein, elastin, casein and albumin, and accounted for most of the non-specific protease activity detected in culture filtrates. The purified enzyme hydrolysed proteins in situ from the outer layer of the egg shell of the host nematode Meloidogyne incognita and exposed its chitin layer. VCPl was secreted by several isolates of V. chlamydosporium and V. lecanii, pathogens of nematodes and insects respectively, but not plantpathogenic species of Verticillium. These observations suggest that VCPl or similar enzyme(s) may play a role in the infection of invertebrates.M and a kcat of 5-8 s-I. It was highly sensitive