Abstract: A lipid delivery system, a virus-like structure (VLS) vaccine constructed therefrom, and a lipid particle capable of encapsulating an mRNA molecule encoding a SARS-CoV-2-specific antigen are provided. After the lipid particle encapsulates an mRNA molecule encoding a SARS-CoV-2 antigen, a SARS-CoV-2 S1 antigen protein can be embedded on a surface of an envelope structure of the lipid under specific buffer conditions to produce a VLS vaccine with an antigen-encoding mRNA molecule encapsulated inside and an outer membrane presenting a required viral antigen protein. The vaccine has a superior specific antibody-inducing ability to a SARS-CoV-2 mRNA vaccine and a polypeptide vaccine, can maintain a long-lasting high antibody level, and can also exhibit excellent immune binding abilities for the emerging different variants.

Abstract: A Saccharomyces cerevisiae strain with high yield of ethyl butyrate and a construction method and an application thereof are provided. The strain is obtained by over-expressing in the starting strain acetyl coenzyme A acyl transferase gene Erg10, 3-hydroxybutyryl coenzyme A dehydrogenase gene Hbd, 3-hydroxybutyryl coenzyme A dehydratase gene Crt, trans-2-enoyl coenzyme A reductase gene Ter, and alcohol acyl transferase gene AAT. Compared to the starting bacteria not producing ethyl butyrate, the yield of ethyl butyrate of the constructed strain reaches 77.33±3.79 mg/L, the yield of the ethyl butyrate of the strain with double copy expression of gene Ter and gene AAT reaches 99.65±7.32 mg/L, increased by 28.9% compared with the EST strain, and 40.93±3.18 mg/L of ethyl crotonate is unexpectedly produced.

Abstract: A Saccharomyces cerevisiae strain with high yield of ethyl butyrate and a construction method and an application thereof are provided. The strain is obtained by over-expressing in the starting strain acetyl coenzyme A acyl transferase gene Erg10, 3-hydroxybutyryl coenzyme A dehydrogenase gene Hbd, 3-hydroxybutyryl coenzyme A dehydratase gene Crt, trans-2-enoyl coenzyme A reductase gene Ter, and alcohol acyl transferase gene AAT. Compared to the starting bacteria not producing ethyl butyrate, the yield of ethyl butyrate of the constructed strain reaches 77.33±3.79 mg/L, the yield of the ethyl butyrate of the strain with double copy expression of gene Ter and gene AAT reaches 99.65±7.32 mg/L, increased by 28.9% compared with the EST strain, and 40.93±3.18 mg/L of ethyl crotonate is unexpectedly produced.