Tannases produced by filamentous fungi are in a family of important hydrolases of gallotannins and have broad industry applications.But until now,the 3-D structures of fungi tannases have not been reported.The protein...Tannases produced by filamentous fungi are in a family of important hydrolases of gallotannins and have broad industry applications.But until now,the 3-D structures of fungi tannases have not been reported.The protein sequence deduced from the cDNA sequence obtained using RT-PCR amplification was identified as tannase through sequence alignment and phylogenetic analysis.Structure models based on the tannase sequence were collected using I-TASSER,and the model with the best match to the surface charge density-pH titration profile was selected as the final structure for tannase from Aspergillusniger N5-5.This work provides an effective method for protein structure research.The structure constructed in this work should be very important to understand the enzyme bioactivities and further developments of fungi tannases.展开更多
In order to develop natural antibacterial agents,the antibacterial activity of Aspergillusnigerxj was investigated.After being cultured in potato dextrose liquid medium liquid medium,mycelia was under heating reflux e...In order to develop natural antibacterial agents,the antibacterial activity of Aspergillusnigerxj was investigated.After being cultured in potato dextrose liquid medium liquid medium,mycelia was under heating reflux extraction with 90% ethanol.Removal of ethanol under reduced pressure gave a residue,to which water was added and then extracted with petroleum ether and ethyl acetate.In vacuo evaporation of the solvents yielded three crude extracts.Then the disc diffusion method was used to measure the antibacterial activity of these extracts.The petroleum ether extract with antibacterial activity was separated by silica gel column chromatography method,then separated and identified by GC-MS after been methyl esterified.At the concentration of 50 mg /mL,the petroleum ether extract of mycelia exhibited inhibitory effect against Staphylococcus aureus.The petroleum ether extract from Aspergillusnigerxj mycelia contained natural substances with antibacterial activity and fatty acids are the main constituents in it.展开更多
基金the National Natural Science Foundation of China (No. 21374117)the 100 Talents Program of Chinese Academy of Sciences for financial support
文摘Tannases produced by filamentous fungi are in a family of important hydrolases of gallotannins and have broad industry applications.But until now,the 3-D structures of fungi tannases have not been reported.The protein sequence deduced from the cDNA sequence obtained using RT-PCR amplification was identified as tannase through sequence alignment and phylogenetic analysis.Structure models based on the tannase sequence were collected using I-TASSER,and the model with the best match to the surface charge density-pH titration profile was selected as the final structure for tannase from Aspergillusniger N5-5.This work provides an effective method for protein structure research.The structure constructed in this work should be very important to understand the enzyme bioactivities and further developments of fungi tannases.
基金Supported by Graduate Student Innovation Fund of Guizhou University(2011012)Guizhou Agricultural Science and Technology Plan Program(20113053)+1 种基金Special Fund of Bijie Circular Economy Research Institute(2010ZK009)Guizhou Science and Technology Fund(20102065)
文摘In order to develop natural antibacterial agents,the antibacterial activity of Aspergillusnigerxj was investigated.After being cultured in potato dextrose liquid medium liquid medium,mycelia was under heating reflux extraction with 90% ethanol.Removal of ethanol under reduced pressure gave a residue,to which water was added and then extracted with petroleum ether and ethyl acetate.In vacuo evaporation of the solvents yielded three crude extracts.Then the disc diffusion method was used to measure the antibacterial activity of these extracts.The petroleum ether extract with antibacterial activity was separated by silica gel column chromatography method,then separated and identified by GC-MS after been methyl esterified.At the concentration of 50 mg /mL,the petroleum ether extract of mycelia exhibited inhibitory effect against Staphylococcus aureus.The petroleum ether extract from Aspergillusnigerxj mycelia contained natural substances with antibacterial activity and fatty acids are the main constituents in it.