Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously cloned the acetone-formation pathway gene, encoding acetoacetate decarboxylase (adc), and butyrate-formation pathway gene, encoding phosphotransbutyrylase (ptb), of Clostridium acetobutylicum ATCC 824 in Escherichia coli. Here we report their subcloning in Bacillus subtilis and transfer to strain ATCC 824 via electrotransformation, where the corresponding enzyme activities were expressed at elevated levels, using pFNK1, a new B. subtilis/C. acetobutylicum shuttle vector. Plasmid pFNK1 was used because shuttle vectors that function in E. coli were unable to electrotransform ATCC 824 unless they became deleted in the E. coli-plasmid regions. The difficulties with shuttle vectors that function in E. coli are probably due to the presence of a restriction endonuclease in ATCC 824. This endonuclease recognizes the sequence 5'-GCNGC-3', which is prevalent in E. coli plasmids but occurs infrequently in pFNK1 and C. acetobutylicum genes. Cloning of genes in C. acetobutylicum is critical for redirecting the cellular metabolism (metabolic engineering) as well as for genetic studies of this industrial organism.
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PMID:Expression of cloned homologous fermentative genes in Clostridium acetobutylicum ATCC 824. 136 30

A 13.6-kilobase (kb) Sau3AI restriction endonuclease fragment of Clostridium acetobutylicum DNA cloned into pBR322 enabled Escherichia coli ato mutants to grow on butyrate as a sole carbon source (But+). Complementation of the ato defect by the recombinant plasmid pJC6 was due to expression of the genes for phosphotransbutyrylase (PTB) and butyrate kinase (BK). Both genes were efficiently expressed in E. coli, as their products were readily detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell extracts. PTB was found to have a polypeptide subunit molecular weight of approximately 31,000, while that of BK was approximately 39,000. Deletion analysis and Tn5 mutagenesis of plasmid pJC7 (a But+ subclone containing a 4.4-kb BamHI fragment from the insert of pJC6) localized the PTB and BK genes within a region spanning approximately 2.9 kb. Preliminary evidence suggests that the two genes may form an operon that is transcribed as a single unit from a promoter of clostridial origin within the 4.4-kb insert of pJC7.
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PMID:Cloning and expression of Clostridium acetobutylicum phosphotransbutyrylase and butyrate kinase genes in Escherichia coli. 284 25