Reagents and methods for cyanobacterial production of bioplastics and biomaterials

A recombinant cyanobacterial host cell, comprising:

• (a) an insertion or deletion in an endogenous slr1125 gene encoding the protein of SEQ ID NO:
• 2 or SEQ ID NO:
• 4, such that the host cell is deficient in expression of the endogenous Slr1125 protein of SEQ ID NO:
• 2 or SEQ ID NO:
• 4;
• and
• (b) an insertion or deletion in a gene encoding an endogenous cyanophycin synthetase gene such that the hos cell is deficient in production of endogenous cyanophycin.