https://www.selleckchem.com/ The copy number of endoglucanase was identified by Droplet Digital PCR and explore the relationship between copy number and protein expression.The engineered Saccharomyces cerevisiae of endoglucanase with copy numbers of 1, 3, 4, 7, 9, 11, 15, 16, 19, 21, 22 and 23 were obtained by rDNA integration, respectively. The results showed that when the copy number was 15, the enzyme activity was the highest, namely 351 U/mL. The engineered strain of Saccharomyces cerevisiae for endoglucanase was successfully constructed, which can provide reference for the heterologous expression of other industrial enzymes.Biological desulfurization is a process in which sulfur compounds are removed from gas and oil using microorganisms. It is a simple process that has mild operating conditions, high desulfurization efficiency, low energy consumption and less environmental pollution. However, there is still a lack of simple and efficient analytical methods for quantitatively analyzing the sulfur compounds in the biological desulfurization process. In order to solve this problem, the analytical method for the simultaneous determination of sulfite, thiosulfate and sulfide in biological desulfurization solutions by pre-column fluorescence derivation using high performance liquid chromatography (HPLC) was developed. The standard curves of sulfur species in this analytical method had good linear relationships with correlation coefficients of 0.999 5, 0.999 7, and 0.999 7 for sulfite, thiosulfate and sulfide, respectively. The detection limits of these sulfur compounds were 0.000 6, 0.000 7 and 0.001 1 μmol/L; the range of recovery rates were 98.17 to 101.9%, 100.9 to 102.6%, and 101.1 to 104.2%; which had good repeatability and stability. The analytical method was simple, efficient and accurate, and could be used to simultaneously determine the sulfur compounds in different biological desulfurization systems.In most insects, polyunsaturated fatty acids (PUFAs) are