| Protein is nutrition to human beings, which consists of twenty different types of amino acids, ten out of which can not be synthesized by human bodies thus have to be taken from food. These types of amino acids are called essential amino acids. Lysine is one of nine essential amino acids. Lysine has many biological functions including: increasing the appetite; enhancing the hemoglobin content in blood and curing peptic ulcer, etc. The lack of lysine in a human being can cause abnormal loss of weight and incomplete growth of bones, and the deficient assimilation of other amino acids, therefore, lysine is called by nutritionist as "the first needed amino acid".Transformation of lysine-rich protein genes from winged bean to Tremella fuciformis which has high nutritional value may enhance the genetically modified Tremella fuciformis nutritional and functional values. Since lysine-rich protein is a multifunctional protein if the tansgenes express correctly, the utilization of protein will also be enhanced.In the study, on the basis of studying the system of genetic transformation of Tremella fuciformis, a lysine-rich protein gene expression vector was constructed, and then transferred into Tremella fuciformis spores with Restriction Enzyme-Mediated DNA Integration (REMI). Molecular evidence demonstrated that lysine-rich protein gene had been integrated into the genome of transgenic Tremella fuciformis strains. Amino acids content testing results also confirmed that lysine content of transgenic strains was elevated comparably.1. Optimization of preparation and regeneration condition of Tremella fuciformis protoplastsOrthogonal design was used for researching the high yield protoplast of Tremella fuciformis. The results showed that the materials (conidia, mycelia and fruit bodies) were the major factor affecting protoplast yield. Using conidia as material, the yield of protoplast could reach 2.75x107/ml, while using mycelia and fruit body material, the yield of protoplast was only 2.5x106/ml and 1.0x106/ml respectively. The optimal digesting temperature was 35.The lywallzyme concentration ranging from 1% to 3%, did not affect the yield of protoplasts significantly. There was also nosignificant difference in the yield of protoplasts from different strains. The effect of osmotic stabilizer (KCI) concentration on regeneration of protoplasts was also studied. The results showed that there was no significant difference in the rate of protoplasts regeneration in different concentrations. KCI concentration from 0.5mol/L to 0.7 mol/L did not show significant difference to regeneration of protoplasts: the highest protoplasts regeneration rate was 32.3% in.2. Selection of auxotrophic strainsInduced effects on the spores of Tremella fuciformis by ultraviolet and r-ray radiations were compared. 48 auxotrophic strains from r-rayed were obtained, but the mutants were not steady. 62 auxotrophic strains were obtained from ultraviolet radiation and two were steady auxotrophs. One of two strains Tau811 was inositol-defect mutant by identification. Lag phase of growth of Tau811 was three days more than wild stains.3. Transformation of lysine-rich protein gene to Tremella fuciformis and its molecular evidenceP35S was incorporated into pBR-lys plasmid instead of promoter Pubi to construct expression vector pCB-lys. Transformation of lysine-rich protein gene to Tremella fuciformis produced many transformants. The results of the test of nuclear rDNA and deficiency diagnosis of nutrients showed that these transformants were yeast-like-conidia. These transformants bring with 35S promoter, Lys gene, GUS gene, hpt gene, nos terminator by PCR determination. The resistance to hygromycin in transformants reached 150ug/ml, and the determination of GUS activity of transformants was positive.4. Determination of the lysine content of transgenic strainsUsing Automatic Amino Acid Analyzer, Amino acids content determination of non-transgenic strain Tau811 and six transgenic strains with high resistance to hygromycin, showed that: the ly...
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