The glyoxylate bypass of Ralstonia eutropha.

نویسندگان

  • Zheng-Xiang Wang
  • Christian O Brämer
  • Alexander Steinbüchel
چکیده

The glyoxylate bypass genes aceA1 (isocitrate lyase 1, ICL1), aceA2 (isocitrate lyase 2, ICL2) and aceB1 (malate synthase, MS1) of Ralstonia eutropha HF39 were cloned, sequenced and functionally expressed in Escherichia coli. Interposon-mutants of all three genes (DeltaaceA1, DeltaaceA2 and DeltaaceB1) were constructed, and the phenotypes of the respective mutants were investigated. Whereas R. eutropha HF39DeltaaceA1 retained only 19% of ICL activity and failed to grow on acetate, R. eutropha HF39DeltaaceA2 retained 84% of acetate-inducible ICL activity, and growth on acetate was not retarded. These data suggested that ICL1 is in contrast to ICL2 induced by acetate and specific for the glyoxylate cycle. R. eutropha HF39DeltaaceB1 retained on acetate as well as on gluconate about 41-42% of MS activity and exhibited retarded growth on acetate, indicating the presence of a second hitherto not identified MS in R. eutropha HF39. Whereas in R. eutropha HF39DeltaaceA1 and R. eutropha HF39DeltaaceA2 the yields of poly(3-hydroxybutyric acid), using gluconate as carbon source, were significantly reduced, R. eutropha HF39DeltaaceB1 accumulated the same amount of this polyester from gluconate as well as from acetate as R. eutropha HF39.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Elucidation of beta-oxidation pathways in Ralstonia eutropha H16 by examination of global gene expression.

Ralstonia eutropha H16 is capable of growth and polyhydroxyalkanoate production on plant oils and fatty acids. However, little is known about the triacylglycerol and fatty acid degradation pathways of this bacterium. We compare whole-cell gene expression levels of R. eutropha H16 during growth and polyhydroxyalkanoate production on trioleate and fructose. Trioleate is a triacylglycerol that ser...

متن کامل

Influence of Matric Potential on Survival and Activity of Genetically Engineered Ralstonia eutropha H850Lr

Although the application of biodegradative genetically engineered micro organisms (GEMs) for bioremediation is very promising, the risks of their release should be assessed before their introduction into the environment. Lux-marked Ralstonia eutropha H850Lr (formerly Alcaligenes eutrophus H850Lr) was introduced into sterile and non-sterile soil microcosms at matric potentials ?2.11, ?30, ?750, ...

متن کامل

Aerobic degradation of methylene blue from colored effluents by Ralstonia eutropha

The present paper has examined the degrading ability of phenol-oxidizing bacterium, Ralstonia eutropha, for biological removal of methylene blue (MB) from aqueous solutions under aerobic conditions. Results show that MB has been extensively eliminated as a co-metabolism in the presence of supplementary carbon (glucose) and nitrogen (yeast extract and peptone) sources and the experimental observ...

متن کامل

Application of the Taguchi Design for Production of Poly(β-hydroxybutyrate) by Ralstonia eutropha

The Taguchi design of experiments was used to test the relative importance of medium components and environmental factors on poly(β-hydroxybutyrate)(PHB) production by Ralstonia eutropha. The optimum condition was obtained as: fructose concentration, 15 g/L; C/N ratio, 7.4; agitation speed 200 rpm; culture time, 40 h; temperature, 25 ° C; seed age, 15 h. At optimu...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • FEMS microbiology letters

دوره 228 1  شماره 

صفحات  -

تاریخ انتشار 2003