The present invention relates to a modified ptxD nucleotide sequence and related uses as a genetic stabilizer and growth selector for the genetic transformation of the chloroplast genome of microalgae and methods for enhance the expression of recombinant proteins of interest in large-scale algal cultivation.

An exemplary embodiment of the present disclosure provides a method of converting formate to a desired compound. The method comprises providing a biocatalyst and formate to form a reaction mixture and reacting at least the biocatalyst with formate to produce a first reaction product.

Phosphite dehydrogenase (ptxD) expression was established as a selectable marker for nuclear and chloroplast genetic selection in Picochlorum renovo and Picochlorum celeri Phosphite was used as a sole phosphorus source in P. renovo and P. celeri. Growth on phosphite led to comparable growth and composition relative to phosphate.

It is an object of an aspect of the present invention to provide (i) transformants, whose proliferation depends on phosphite, of various species of organism and (ii) a method for detecting the presence of a reduced phosphorous compound with use of such a transformant. Use is made of a transformant which is defective in functions of a gene encoding a phosphate transporter protein and a gene encoding a phosphate ester transporter protein and into which a gene encoding a hypophosphite transporter protein is introduced, a signal peptide of a hypophosphite binding protein being substituted with a signal peptide derived from a host or a species of organism closely related to the host.

The present disclosure relates to genetically modified cells containing mitochondria that have been transformed with a polynucleotide encoding a phosphite dehydrogenase enzyme, such that the cells can utilize phosphite as a phosphorus source.

The present invention provides engineered ketoreductase and phosphite dehydrogenase enzymes having improved properties as compared to a naturally occurring wild-type ketoreductase and phosphite dehydrogenase enzymes, as well as polynucleotides encoding the engineered ketoreductase and phosphite dehydrogenase enzymes, host cells capable of expressing the engineered ketoreductase and phosphite dehydrogenase enzymes, and methods of using the engineered ketoreductase and phosphite dehydrogenase enzymes to synthesize a chiral catalyst used in the synthesis of antiviral compounds, such as nucleoside inhibitors. The present invention further provides methods of using the engineered enzymes to deracemize a chiral alcohol in a one-pot, multi-enzyme system.

The present invention provides engineered ketoreductase and phosphite dehydrogenase enzymes having improved properties as compared to a naturally occurring wild-type ketoreductase and phosphite dehydrogenase enzymes, as well as polynucleotides encoding the engineered ketoreductase and phosphite dehydrogenase enzymes, host cells capable of expressing the engineered ketoreductase and phosphite dehydrogenase enzymes, and methods of using the engineered ketoreductase and phosphite dehydrogenase enzymes to synthesize a chiral catalyst used in the synthesis of antiviral compounds, such as nucleoside inhibitors. The present invention further provides methods of using the engineered enzymes to deracemize a chiral alcohol in a one-pot, multi-enzyme system.