The present disclosure provides recombinant Staphylococcus bacterium (e.g. S. epidermidis) that are dependent on D-alanine for growth. In one aspect, the disclosure features a recombinant Staphylococcus bacterium comprising two inactivated alanine racemase genes (Δalr1Δalr2); and an inactivated D-alanine aminotransferase (dat) gene. In another aspect, the disclosure features a method of making the recombinant Staphylococcus bacterium.

The present disclosure provides recombinant Staphylococcus bacterium (e.g. S. epidermidis) that are dependent on D-alanine for growth. In one aspect, the disclosure features a recombinant Staphylococcus bacterium comprising two inactivated alanine racemase genes (Δalr1Δalr2); and an inactivated D-alanine aminotransferase (dat) gene. In another aspect, the disclosure features a method of making the recombinant Staphylococcus bacterium.

The present disclosure provides recombinant Staphylococcus bacterium (e.g. S. epidermidis) that are dependent on D-alanine for growth. In one aspect, the disclosure features a recombinant Staphylococcus bacterium comprising two inactivated alanine racemase genes (Δalr1Δalr2); and an inactivated D-alanine aminotransferase (dat) gene. In another aspect, the disclosure features a method of making the recombinant Staphylococcus bacterium. In another aspect, the disclosure features a method of treating or preventing a rash in a subject, comprising administering to the subject a population of the recombinant Staphylococcus bacterium of any one of the aspects or embodiments described herein, in an effective amount to treat or prevent the rash in the subject.

The present invention provides Listeria vaccine strains that express a heterologous antigen and a metabolic enzyme, and methods of generating same.

The present disclosure provides recombinant Staphylococcus bacterium (e.g. S. epidermidis) that are dependent on D-alanine for growth. In one aspect, the disclosure features a recombinant Staphylococcus bacterium comprising two inactivated alanine racemase genes (?alr1?alr2); and an inactivated D-alanine aminotransferase (dat) gene. In another aspect, the disclosure features a method of making the recombinant Staphylococcus bacterium.

A new mutant of D-amino acid transaminase, based on supercomputing-assisted technology, belongs to the fields of computational biology, computer-aided design, and enzyme engineering technology, and specifically relates to mutants of D-amino acid transaminase obtained based on supercomputing-assisted technology and applications thereof. Compared to the wild-type enzyme, the aforementioned mutant of D-amino acid transaminase exhibits a half-life (t.sub.1/2) of over 12 hours at 40? C., while it is only 8.8 minutes for the wild-type D-amino acid transaminase. The half-inactivation temperature (T.sub.50.sup.5) of the mutant is 45.3? C., approximately 5.4? C. higher than that of the wild-type D-amino acid transaminase. This substantially enhances its thermal stability, enzymatic activity, etc., effectively broadening its application fields and scope. The mutant has a wide range of industrial applications and thus holds substantial practical value.

Provided herein are an apparatus and process for manufacturing a formulation comprising a drug substance, said drug substance comprising a recombinant Listeria strain comprising a prostate specific antigen (PSA) or a chimeric HER2 antigen fused to a Listeriolysin O (LLO) protein fragment.

Disclosed herein are recombinant Listeria strains comprising nucleotides encoding two or more heterologous antigens each fused to a truncated LLO, an N-terminal ActA or a PEST-sequence, methods of preparing same, and methods of inducing an immune response, and treating, inhibiting, or suppressing cancer or tumors comprising administering same.

A new mutant of D-amino acid transaminase, based on supercomputing-assisted technology, belongs to the fields of computational biology, computer-aided design, and enzyme engineering technology, and specifically relates to mutants of D-amino acid transaminase obtained based on supercomputing-assisted technology and applications thereof. Compared to the wild-type enzyme, the aforementioned mutant of D-amino acid transaminase exhibits a half-life (t.sub.1/2) of over 12 hours at 40 C., while it is only 8.8 minutes for the wild-type D-amino acid transaminase. The half-inactivation temperature (T.sub.50.sup.15) of the mutant is 45.3 C., approximately 5.4 C. higher than that of the wild-type D-amino acid transaminase. This substantially enhances its thermal stability, enzymatic activity, etc., effectively broadening its application fields and scope. The mutant has a wide range of industrial applications and thus holds substantial practical value.

The present invention provides Listeria vaccine strains that express a heterologous antigen and a metabolic enzyme, and methods of generating same.