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Fermentation of 6-Deoxyhexoses by Bacillus macerans
1Experimental Station, Central Research and Development Department, E. I. du Pont de Nemours & Company, Wilmington, Delaware 19898.
Applied and Environmental Microbiology
|February 1, 1984
Summary
Bacillus macerans ferments 6-deoxyhexoses like l-rhamnose into 1,2-propanediol (PD) under anaerobic conditions. This specific fermentation pathway yields PD efficiently, unlike hexose fermentation.
Area of Science:
- Microbiology
- Biochemistry
- Metabolic Engineering
Background:
- * Bacillus macerans ATCC 7068 ferments various sugars under anaerobic conditions.
- * Understanding microbial fermentation pathways is crucial for developing sustainable bioprocesses.
Purpose of the Study:
- * To investigate the anaerobic fermentation of 6-deoxyhexoses by Bacillus macerans.
- * To elucidate the metabolic pathway responsible for 1,2-propanediol (PD) production.
Main Methods:
- * Anaerobic fermentation of 6-deoxyhexoses (l-rhamnose, l-fucose, d-fucose) and hexoses (d-glucose, l-mannose) using Bacillus macerans ATCC 7068.
- * Measurement of fermentation products including 1,2-propanediol (PD), acetone, H(2), CO(2), and ethanol.
- * Analysis of cell extracts for enzymatic activities, including lactaldehyde reductase.
Main Results:
- * Bacillus macerans produced PD, acetone, H(2), CO(2), and ethanol from 6-deoxyhexoses, with PD yield proportional to l-rhamnose concentration.
- * No PD was produced from hexoses, despite active fermentation.
- * Fermentation of l-rhamnose resulted in reduced yields of H(2), CO(2), and cell mass compared to d-glucose.
- * Cell extracts showed pyridine nucleotide-linked lactaldehyde reductase activity converting lactaldehyde to PD.
Conclusions:
- * Bacillus macerans utilizes an Embden-Meyerhof pathway for 6-deoxyhexose catabolism.
- * Lactaldehyde is an intermediate formed via aldolase cleavage, subsequently reduced to PD.
- * This pathway offers a specific route for 1,2-propanediol production from 6-deoxyhexoses.
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