Tartrate catabolism gene

DETAILED DESCRIPTION What is claimed is: 1.
A method for making an incompetent unicellular microorganism host competent to utilize L-tartrate as a carbon source, said method comprising introducing in vitro a plasmid conferring the ability to utilize L-tartrate into the host, said plasmid being capable of expressing a tartrate catabolism gene derived from plasmid pTAR.
2.
An incompetent unicellular microorganism host made competent to utilize L-tartrate by the method of claim 1.
3.
A prokaryotic host as in claim 2.




Description:
BACKGROUND OF THE INVENTION The ability to catabolize tartrate and utilize tartrate as a carbon source is very rare in microorganisms.
It would be desirable to identify and isolate a gene which is able to confer the ability to utilize tartrate on a suitable host.
For example, yeast used to ferment juice to alcohol are unable to utilize tartrate which is a byproduct of fermentation.
Introduction of a functional tartrate gene into yeast would allow the organism to utilize this additional energy source, leading to the production of additional alcohol from a given amount of juice.
The trait would also be useful when it is desired to produce wine free of tartrate.
SUMMARY OF THE INVENTION DNA sequences expressing polypeptides having the ability to catabolize L-tartrate are provided.
Vectors incorporating the DNA sequences are used to transform a susceptible host to utilize L-tartrate as a carbon source.
BRIEF DESCRIPTION OF THE DRAWING FIG.
1 illustrates the restriction pattern of pTAR giving letter designations for the fragments and indicating the relative sizes.
DESCRIPTION OF THE SPECIFIC EMBODIMENTS The DNA sequences of the present invention appear to be less than about 20 kbp, probably less than about 10 kbp, and can be derived directly or indirectly from the TAR gene found in the pTAR plasmid of certain strains of Agrobacterium tumefaciens, as well as from the genome of a certain large cryptic plasmid (exceeding 200 megadaltons) found in certain biotype 3 strains of A