Expression Of Trichoderma Reesei Swo1Gene In Aspergillus Niger

Swollenin is a kind of protein found in the filamentous fungus called Trichoderma reesei which has a leavening role to the cell wall of plants.It can reduce the cell wall with inactivation extending, similar to plant expansion, it was called swollenin because of the expansion effect to cotton fiber, its gene name is swol.Swollienin can synergistically degrade cellulose, improve the efficiency of the filter paper, make the filter paper cellulose fiber and its loose structure, which has an important application foreground in industrial production.The experiment takes Trichoderma reesei strain QM9414as gene donor, takes Aaspergillus niger CICC2462as receptor strains, clones swollenin gene(swo1), constructs Aspergillus niger to express vector pSZHGS-swol, carries out genetic transformation on Aspergillus niger by Agrobacterium mediated method, in order to achieve high expression of swollenin gene in Aspergillus niger, effect of cellulose material and cellulase degrades, so as to explore a new way for the industrialization production.The main research harvests are as follows:1. Construction of pSZHGS-swo1expression vectorBy taking Trichoderma reesei strain as gene donor, using PCR technology, then get expansin gene swol by cloning, The swol gene plasmid which is connected by T carrier with expression vector pSZHGS respectively with NheI, HindⅢ restriction enzyme digestion and connection, construct expression vector pSZHGS-swol of Aspergillus niger.2. Aspergillus niger transformants of swol gene and homologous recombinant transformant screeningThe Aspergillus niger expression vector pSZHGS-swol by freeze-thaw method transformed into Agrobacterium AGL1, and using Agrobacterium tumefaciens mediated method for genetic transformation of Aspergillus niger CICC2462.Co PCR test was carried out on16strains of resistant colonies, there were4strains colony can be amplified3742bp band, as the positive transformants, the positive rate of swol gene transformed is25%.Using homologous recombination primer PCR identification of the selected4strains,3strains were amplified results can be roughly1701bp of the band, shows that the3strains for homologous recombination and transformation, pSZHGS-swol transformation and homologous recombination rate is75%.3. Disintegration test swollenin protein on filter paper The homologous recombination strains screened by liquid fermentation,take the processed fermentation supernatant to filter paper cellulase disintegration test.The results show that, recombinant of the fermentation supernatant of strain pSZHGS-swol to cellulase degradation of filter paper, making it more bulky and disintegrating effect is obvious, the protein has obvious bulky paper fibers.