Microorganism strains that produce a high proportion of alternan to dextran

• US 5,702,942 A
• Filed: 06/06/1995
• Issued: 12/30/1997
• Est. Priority Date: 08/02/1994
• Status: Expired due to Term

• Current Assignee: United States Of America As Represented By The Secretary Of The Army (Government of the United States of America)
• Original Assignee: United States Department Of Agriculture
• Inventors: Cote, Gregory L., Leathers, Timothy D., Hayman, G. Thomas
• Primary Examiner(s): Marx, Irene
• Application Number:
  US08/474,637
• Time in Patent Office: 938 Days
• Field of Search: 435/252.9, 435/101, 435/251.1
• US Class Current: 435/252.9
• CPC Class Codes: C12N 1/205 Bacterial isolates
• CPC Class Codes: C12N 9/1051 Hexosyltransferases (2.4.1)
• CPC Class Codes: C12P 19/04 Polysaccharides, i.e. compounds containing more than five saccharide radicals attached to each other by glycosidic bonds
• CPC Class Codes: C12P 19/18 produced by the action of a glycosyl transferase, e.g. alpha-, beta- or gamma-cyclodextrins
• CPC Class Codes: C12Q 1/04 Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor C12Q1/6897 takes precedence
• CPC Class Codes: C12R 2001/01 Bacteria or Actinomycetales ; using bacteria or Actinomycetales
• CPC Class Codes: G01N 2400/14 alpha-D-Glucans, i.e. having alpha 1,n (n=3,4,6) linkages between saccharide units, e.g. pullulan
• CPC Class Codes: G01N 2400/22 Dextran

Abstract

A rapid screening procedure to select microorganism strains that produce a high proportion of alternan to dextran and a high proportion of alternansucrase to dextransucrase is described. Strains selected by the method are useful to produce a high proportion of alternansucrase to dextransucrase and to produce a high proportion of alternan to dextran, either fermentatively by cultivation of the strains on sucrose, or enzymatically by using alternansucrase produced by the strains of the invention. The selected strains can also be used to obtain microorganism strains having further improvements.

Claims

1. A biologically pure culture of a bacterial strain that produces a greater proportion of alternan to dextran, said strain selected from the group-consisting of Leuconostoc mesenteroides NRRL B-21138 and L. mesenteroides NRRL B-21297.

2. The biologically pure culture of claim 1 wherein said strain is Leuconostoc mesenteroides NRRL B-21138.

3. The biologically pure culture of claim 1 wherein said strain is Leuconostoc mesenteroides NRRL B-21297.