Engineered primate cystine/cysteine degrading enzymes as antineogenic agents
View Patent ↗Methods and compositions related to the engineering of a protein with L-cyst(e)ine degrading enzyme activity are described. For example, in certain aspects there may be disclosed a modified cystathionine-γ-lyase comprising one or more amino acid substitutions and capable of degrading L-cyst(e)ine. Furthermore, certain aspects of the invention provide compositions and methods for the treatment of cancer with L-cyst(e)ine using the disclosed proteins or nucleic acids.
1. An isolated, modified primate cystathionine-γ-lyase (CGL) enzyme having at least one substitution relative to a native primate CGL amino acid sequence (see SEQ ID NOs: 1 and 7-10), said at least one substitution including a threonine at position 59 of the native primate CGL sequence.
2. The enzyme of claim 1 , further comprising a valine substitution at position 339.
3. The enzyme of claim 1 , further comprising a heterologous peptide segment.
4. The enzyme of claim 3 , wherein the heterologous peptide segment is an XTEN peptide, an IgG Fc, an albumin, or an albumin binding peptide.
5. The enzyme of claim 1 , wherein the enzyme is coupled to polyethylene glycol (PEG).
6. The enzyme of claim 5 , wherein the enzyme is coupled to PEG via one or more lysine or cystine residues.
7. An isolated, modified primate cystathionine-γ-lyase (CGL) enzyme having at least two substitutions relative to a native primate CGL amino acid sequence (see SEQ ID NOs: 1 and 7-10), said at least two substitutions including a threonine at position 59 and a valine at position 339 of the native primate CGL sequence.
8. A nucleic acid comprising a nucleotide sequence encoding the enzyme of claim 1 .
9. The nucleic acid of claim 8 , wherein the nucleic acid is codon optimized for expression in bacteria, fungus, insects, or mammals.
10. An expression vector comprising the nucleic acid of claim 8 .
11. A host cell comprising the nucleic acid of claim 8 .
12. The host cell of claim 11 , wherein the host cell is a bacterial cell, a fungal cell, an insect cell, or a mammalian cell.