The present invention relates to the field of genetic engineering, particularly to a recombinant expression vector for rapidly screening the high expression strains and a method for rapidly screening high expression strains. In the invention, an exogenous red fluorescent protein and Aspergillus fumigatus cell surface protein localization signal are fused and expressed, and the fusion gene (DsRed-AfMP1) is integrated into the genome of Trichoderma reesei, so as to construct a strain displaying red fluorescent protein on the surface of Trichoderma reesei. By sorting Trichoderma reesei strains with red fluorescent protein on the surface by flow cytometry, genes beneficial to the improvement of cellulase activity can be quickly isolated.

A method for quantitative or qualitative determination of at least one fungus of interest in a sample where use is made of an assay that determines enzymatic activity derived from the fungus. In addition, an enzyme inhibitor that preferentially inhibits the corresponding enzymatic activity in other cells potentially present in the sample is added so as to minimize false positive enzyme activity measurements from these other cells. Also a kit comprising a substrate for the enzyme to be determined and an inhibitor of the enzyme activity is provided. Moreover, the invention also relates to a method for determination of relative concentrations/numbers of fungal cells in samples comprising other biomass

The present invention relates to the field of genetic engineering, particularly to a recombinant expression vector for rapidly screening the high expression strains and a method for rapidly screening high expression strains. In the invention, an exogenous red fluorescent protein and Aspergillus fumigatus cell surface protein localization signal are fused and expressed, and the fusion gene (DsRed-AfMP1) is integrated into the genome of Trichoderma reesei, so as to construct a strain displaying red fuorescent protein on the surface of Trichoderma reesei. By sorting Trichoderma reesei strains with red fluorescent protein on the surface by flow cytometry, genes beneficial to the improvement of cellulase activity can be quickly isolated.