RESUMO
Background: Phytate is an anti-nutritional factor in plants, which catches the most phosphorus contents and some vital minerals. Therefore, Phytase is added mainly as an additive to the monogastric animals' foods to hydrolyze phytate and increase absorption of phosphorus
Objectives: Y. intermedia phytase is a new phytase with special characteristics such as high specific activity, pH stability, and thermostability. Our aim was to clone, express, and characterizea codon optimized Y. intermedia phytase gene in E. coli
Materials and Methods: The Y. intermedia phytase gene was optimized according to the codon usage in E. coli. The sequence was synthesized and sub-cloned in pET-22b [+] vector and transformed into E. coli Bl21 [DE3]. The protein was expressed in the presence of IPTG at a final concentration of 1 mM at 30[degree]C. The purification of recombinant protein was performed by Ni2+ affinity chromatography. Phytase activity and stability were determined in various pH and temperatures
Results: The codon optimized Y. intermedia phytase gene was sub-cloned successfully. The expression was confirmed by SDS-PAGE and Western blot analysis. The recombinant enzyme [approximately 45 kDa] was purified. Specific activity of enzyme was 3849 [U.mg-1] with optimal pH 5 and optimal temperature of 55[degree]C. Thermostability [80[degree]C for 15 min] and pH stability [3-6] of the enzyme were 56 and more than 80%, respectively
Conclusions: The results of the expression and enzyme characterization revealed that the optimized Y. intermedia phytase gene has a good potential to be produced commercially and to be applied in animals' foods industry
RESUMO
In recent years, the quality of human sperm and its fertility potential have decreased dramatically. This may suggest that the quality of semen has deteriorated partly due to the effects of increasing toxic factors in the environment. Infertility remains a major problem in society, and recent data show that as many as one in four couples is trying to solve the problem. Male infertility accounts for 40% of infertility cases. Many environmental agents such as tobacco smoke and nicotine and genetic factors have been implicated in the poor sperm function and resultant infertility. The article is a review of the impacts of nicotine on human fertility potential. According to our results, nicotine is proved to be a potent pro-oxidant to the biological samples like spermatozoa population and is able to alter the fertility potential of man by inducing the membrane impairments, altering the GSH metabolism cycle, changing the sperm morphology and motility, and also inducing the DNA fragmentation. Antioxidant supplementation could reverse partially the negative effect of nicotine on sperm functions. However, further studies are necessary to illuminate the other dark sides of nicotinic infertility in human spermatozoa.