Patent · US Expired

Zymomonas pentose-sugar fermenting strains and uses thereof

US7223575B2 · kind B2 · utility

34Cited by
3References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 27, 2002
Grant dateMay 29, 2007
Priority date
Expiry dateJun 30, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02E50/10
  • WIPO fieldBiotechnology
  • WIPO sectorChemistry

Abstract

Disclosed in the present invention is a Zymomonas integrant and derivatives of these integrants that posses the ability to ferment pentose into ethanol. The genetic sequences encoding for the pentose-fermenting enzymes are integrated into the Zymomonas in a two-integration event of homologous recombination and transposition. Each operon includes more than one pentose-reducing enzyme encoding sequence. The integrant in some embodiments includes enzyme sequences encoding xylose isomerase, xylulokinase, transketolase and transketolase. The Zymomonas integrants are highly stable, and retain activity for producing the pentose-fermenting enzyme for between 80 to 160 generations. The integrants are also resistant to acetate inhibition, as the integrants demonstrate efficient ethanol production even in the presence of 8 up to 16 grams acetate per liter media. These stably integrated sequences provide a unique Zymomonas that may then be used for the efficient conversion of pentose sugars (xylose, arabinose) to ethanol. Method of using the Zymomonas integrants and derivatives thereof in production of ethanol from cellulosic feedstock is also disclosed. The invention also provides a method fo…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.