Abstract: Water-soluble polysaccharide polymers are provided including a polymer composed of repeating pentamer units having a D-glucose:D-mannose:D-glucuronic acid ratio of about 2:2:1, and a polymer composed of repeating tetramer units having a D-glucose:D-mannose:D-glucuronic acid ratio of about 2:1:1. The D-glucose moieties are linked in a beta-?1,4! configuration. The inner D-mannose moieties are linked in an alpha-?1,3! configuration, generally to alternate glucose moieties. The D-glucuronic acid moieties are linked in a beta-?1,2! configuration to the inner mannose moieties. The outer mannose moieties are linked to the glucuronic acid moieties in a beta-?1,4! configuration. Also an isolated acetylase deficient mutant of Xanthomonas is used in a process to produce the polysaccharide.

Abstract: A novel neurotrophic factor referred to as glial cell line-derived neurotrophic factor (GDNF) has been identified and isolated from serum free growth conditioned medium of B49 glioblastoma cells. Rat and human genes encoding GDNF have been cloned and sequenced. A gene encoding GDNF has been subcloned into a vector and the vector has been used to transform a host cell in order to produce biologically active GDNF in a recombinant DNA process. Antibodies to GDNF are disclosed, as well as methods for identifying members of the GDNF family of neurotrophic factors.

Abstract: A recombinant-DNA mediated method for the synthesis of sugar nucleotides is disclosed. This method utilizes portable DNA sequences capable of directing the microbial synthesis of various enzymes that catalyze the synthesis of sugar nucleotides, including UDP-glucose, UDP-glucuronic acid and GDP-mannose. The sugar moieties of these sugar nucleotides may subsequently be incorporated into industrially-useful polysaccharides such as xanthan gum. It has been found that vectors containing the portable DNA sequences described herein are capable both of causing sugar nucleotide production in microorganisms previously incapable of such synthesis and of causing increased sugar nucleotide production in organisms capable of synthesizing small quantities of these compounds. In particular, plasmids pAS7, pAS9 and pTS13 are disclosed. These plasmids are capable of directing sugar nucleotide synthesis in various hosts, including Xanthomonas sp. such as X. campestris and other organisms such as E.

Abstract: Methods for the recombinant-DNA mediated production of xanthan gum and gum variants structurally related to xanthan are disclosed. The methods in part involve the synthesis of these polysaccharides in anaerobic and/or denitrifying hosts.In particular, plasmids pX209 and pRK290-H366 are disclosed which contain the genes, isolated from X. campestris, encoding Transferase I, Transferases II, Transferase III, Transferase IV, Transferase V, Ketalase, Acetylase and Polymerase. These plasmids have been deposited in the American Type Culture Collection under Accession Nos. 67051 and 67049, respectively.

Abstract: Variant xanthan gums are provided which include a water-soluble polysaccharide polymer comprising repeating pentamer units having a D-glucose:D-mannose:D-glucuronic acid ratio of about 2:2:1, and a water-soluble polysaccharide polymer comprising repeating tetramer units having a D-glucose:D-mannose:D-glucuronic acid ratio of about 2:1:1. The D-glucose moieties are linked in a beta- 1,4! configuration. The inner D-mannose moieties are linked in an alpha- 1,3! configuration, generally to alternate glucose moieties. The D-glucuronic acid moieties are linked in a beta- 1,2! configuration to the inner mannose moieties. The outer mannose moieties are linked to the glucuronic acid moieties in a beta- 1,4! configuration. Processes for preparing the polysaccharide polymers are also provided.