PubMed HealthSearch

PubMed · 1366548

Microbial processes for ascorbic acid biosynthesis: a review.

Abstract

L-Ascorbic acid is an important product currently made using the Reichstein process, which is mainly chemical. Recently, bacteria have been identified that are able to transform in a very efficient way glucose to 2,5-keto-D-gluconic acid and this product to 2-keto-L-idonic acid, precursor of L-ascorbic acid. When the corresponding strains are used together, it is possible to get 2-keto-L-idonic acid directly from glucose. Moreover, new strains have been constructed by introducing a gene from a strain responsible for the second step into a strain responsible for the first step. By using one of the new strains, the transformation can be performed in a single step with only one strain. However, the classical process still remains the most competitive.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

J Boudrant. 1990. Microbial processes for ascorbic acid biosynthesis: a review.. https://doi.org/10.1016/0141-0229(90)90159-n

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Homology in the structure and the prosthetic groups between two different terminal ubiquinol oxidases, cytochrome a1 and cytochrome o, of Acetobacter aceti.

Acetobacter aceti produces two different terminal oxidases dependent on the culture conditions, shaking and static cultures. Cells grown on shaking culture contain cytochrome a1, while cytochrome o is present in cells grown on static culture. Cytochrome a1 and cytochrome o of A. aceti were compared especially with respect to the protein structure and the prosthetic groups. Cytochrome a1 exhibited lower CN sensitivity and higher affinity for O2 than cytochrome o. Both terminal oxidases consisted of four nonidentical polypeptides of which the molecular sizes were identical between both enzymes. Cytochrome a1 cross-reacted with an antibody raised against cytochrome o at the same level as cytochrome o did, and an antibody elicited against cytochrome a1 cross-reacted with both cytochrome o and cytochrome a1 at the same intensity, which indicates that both oxidases are indistinguishable immunochemically. Furthermore, almost the same peptide mapping pattern with chymotrypsin was observed in subunit I and in subunit II between both terminal oxidases, and the amino-terminal sequences in the subunit II of both oxidases were identical at least in their 10 amino acids. As for the prosthetic groups, both oxidases were shown to contain two heme-irons and one copper atom. Further, high performance liquid chromatography analysis of the heme moieties extracted from both the purified enzymes indicated that cytochrome a1 contains hemes b and a at a ratio of 1 to 1, whereas cytochrome o contains the same amounts of hemes b and o. Thus, data indicate that cytochrome a1 and cytochrome o of A. aceti are cytochrome ba and cytochrome bo ubiquinol oxidases, respectively, and that both oxidases have a closely similar protein structure and prosthetic groups, in which only heme a in the heme/copper binuclear center of cytochrome a1 is replaced by heme o in that of cytochrome o.

Acetobacter

Isolation of a new restriction enzyme, ApaCI, an isoschizomer of BamHI produced by Acetobacter pasteurianus.

A new Type II restriction endonuclease ApaCI purified from Acetobacter pasteurianus is an isoschizomer of BamHI that cleaves at the nucleotide sequence 5'-G/GATCC-3' of double-stranded DNA. The single restriction activity present in this strain permits rapidly purified 30,000 units of cleavage activity from 10 g of freshly harvested cells. The resulting ApaCI preparation is free of contaminant nuclease activities that might interfere with in vitro manipulation of DNA.

Acetobacter