L-sorbose dehydrogenase and novel L-sorbosone dehydrogenase obta

Details L-sorbose dehydrogenase and novel L-sorbosone dehydrogenase obta L-sorbose dehydrogenase and novel L-sorbosone dehydrogenase obta

1995-11-01

1998-05-19

Prouty, Rebecca E.

Chemistry: molecular biology and microbiology

Enzyme , proenzyme; compositions thereof; process for...

Oxidoreductase

435189, 435243, 43525233, 4353201, 435325, 435410, 435138, 435147, 536 232, C12N 902, C12N 904, C12N 100, C07H 2104

Patent

active

057534810

DESCRIPTION:

BRIEF SUMMARY
TECHNICAL FIELD

The present invention relates to a novel L-sorbose dehydrogenase (hereinafter referred to as SDH) and a novel L-sorbosone dehydrogenase (hereinafter referred to as SNDH) both derived from Gluconobacter Oxydans T-100. More particularly, the present invention relates to a novel SDH, a novel SNDH, a DNA encoding same, an expression vector containing said DNA, a host cell transformed (transfected) with said expression vector, and the production of the SDH and SNDH by culturing the host cell.
The SDH and SNDH of the present invention are enzymes useful for producing 2-keto-L-gulonic acid.


BACKGROUND ART

2-Keto-L-gulonic acid (hereinafter referred to as 2KLGA) is a key intermediate in the synthesis of L-ascorbic acid. For industrial production, 2KLGA is chemically synthesized from L-sorbose by oxidation according to the Reichstein's method.
On the other hand, it is well known that many microorganisms have an ability to convert L-sorbose to 2KLGA through a two-step enzymatic oxidation by SDH and SNDH. Namely, SDH catalyzes the oxidation of L-sorbose to L-sorbosone, and SNDH catalyzes the oxidation of L-sorbosone to 2KLGA. However, because of the low productivity of 2KLGA obtained by using these microorganisms, they have not been applied to the industrial production yet.
It is desirable to provide efficient and simplified methods for the production of 2KLGA.


DISCLOSURE OF THE INVENTION

In an attempt to accomplish the above-mentioned objects, the inventors of this invention conducted intensive studies to find an SDH and an SNDH having preferable properties, and succeeded in producing a novel SDH and a novel SNDH having desirable properties for producing 2KLGA and developed the studies, which resulted in the completion of the present invention.
Accordingly, the present invention relates to a novel SDH derived from Gluconobacter oxydans T-100 (FERM BP-4188), which is characterized by: sequence shown in the Sequence Listing, Sequence No. 1 to be mentioned later.
The present invention also relates to a novel SNDH derived from Gluconobacter oxydans T-100, which is characterized by: acid)SEQ ID NO: 6. The present invention further relates to an SNDH having an amino acid sequence shown in the Sequence Listing, Sequence No. 2.
The present invention also relates to a DNA which encodes the above-mentioned SDH and/or SNDH, an expression vector which contains said DNA, a host cell transformed (transfected) by said expression vector and a process for producing the SDH and/or SNDH, which comprises culturing said host cell (transformant) in a medium and recovering the SDH and/or SNDH from the resulting culture.
The Gluconobacter oxydans T-100 to be used in the present invention is a 2KLGA-high-producing mutant derived from Gluconobacter oxydans G716 (wild strain) by N-methyl-N'-nitro-N-nitrosoguanidine (NTG) mutagenesis in a conventional manner.
The Gluconobacter oxydans G716 was isolated from a persimmon, and has the following morphological and physiological properties. The method described in Bergey's Manual of Systematic Bacteriology Vol. 1 (1984) and the method described in Manual for Identification to Medical Bacteria (S. T. Cowan, 2nd. Edition, 1985) were principally employed for the taxonomic study.
The Gluconobacter oxydans G716 is a Gram-negative, motile bacterium. The cell shapes are rod, occurring both singly and in pairs, and rarely in chains.


______________________________________ Morphological characteristics of Gluconobacter oxydans G716 ______________________________________ Gram stain negative color of colony pale spore negative cell shape rod motility positive flagella 3-8 polar flagella ______________________________________
Physiological characteristics of the Gluconobacter oxydans G716 are summarized in the following table.


______________________________________ Physiological characteristics of Gluconobacter oxydans G716 Conditions Characteristics ______________________________________ growth in air + at 4.degree. C. - at 22.degree. C. + at 30.degree. C

REFERENCES:
patent: 4902617 (1990-02-01), Fujiwara et al.
patent: 4916069 (1990-04-01), Fujiwara et al.
patent: 5082785 (1992-01-01), Manning et al.

Affiliated with

Also associated with

Rating

L-sorbose dehydrogenase and novel L-sorbosone dehydrogenase obta does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with L-sorbose dehydrogenase and novel L-sorbosone dehydrogenase obta, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and L-sorbose dehydrogenase and novel L-sorbosone dehydrogenase obta will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1852115