.beta.-glucuronidase and glucuronide permease gene system

A method of monitoring activity of a controller element in a host cell, comprising:

• (a) introducing into the host cell a DNA construct, the DNA construct comprising DNA encoding beta-glucuronidase and a DNA sequence of the controller element;
• wherein the DNA encoding beta-glucuronidase (a) encodes a protein comprising the amino acid sequence as depicted in FIG. 2 or (b) hybridizes under stringent conditions to the complement of nucleotides 300 to 2105 as depicted in FIG. 2 and which encodes a functional beta-glucuronidase, and
• wherein the DNA encoding beta-glucuronidase is under direction of the controller element;
• and
• (b) detecting the presence of beta-glucuronidase activity, thereby monitoring activity of the controller element.

A method for transforming a host cell with a gene of interest or portion thereof, comprising:

• (a) introducing into the host cell a DNA construct, file DNA construct comprising DNA encoding beta-glucuronidase mad DNA encoding a product of the gene of interest or a portion thereof, such that the DNA construct integrates into the genome of the host cell;
• wherein the DNA encoding beta-glucuronidase (i) encodes a protein comprising the amino acid sequence as depicted in FIG. 2 or (ii) hybridizes under stringent conditions to the complement of nucleotides 300 to 2105 as depicted in FIG. 2 and which encodes a functional beta-glucuronidase;
• and
• (b) detecting the presence of beta-glucuronidase activity, thereby establishing that the host cell is transformed.

A method of releasing a compound from a glucuronide in a host cell, comprising:

• (a) introducing into the host cell a DNA construct, the DNA construct comprising DNA encoding beta-glucuronidase;
• wherein the DNA encoding beta-glucuronidase (a) encodes a protein comprising the amino acid sequence as depicted in FIG. 2 or (b) hybridizes under stringent conditions to the complement of nucleotides 300 to 2105 as depicted in FIG. 2 and which encodes a functional beta-glucuronidase;
• and
• (b) exposing the host cell to the glucuronide, wherein the glucuronide is cleaved by the beta-glucuronidase, such that the compound is released.

A method of releasing a compound from a glucuronide in a host cell expressing endogenous beta-glucuronidase, comprising:

• (a) introducing into the host cell expressing endogenous beta-glucuronidase a DNA construct, the DNA construct comprising DNA encoding glucuronide permease,
• wherein the DNA encoding the glucuronide permease comprises the amino acid sequence as depicted in FIG. 15, or hybridizes trader stringent conditions to the complement of the sequence comprising nucleotides 94-1464 as depicted in FIG. 15 and which encodes a functional glucuronide permease;
• and
• (b) exposing the cell to a glucuronide, wherein the glucuronide is cleaved by the beta-glucuronidase, such that the compound is released.