Characterization and regulation of the speA gene in Escherichia coli

In Escherichia coli, the speA gene encodes biosynthetic arginine decarboxylase (ADC), the first enzyme in a putrescine biosynthetic pathway. ADC converts arginine to agmatine, which is hydrolyzed by agmatine ureohydrolase, encoded by the speB gene, to putrescine and urea. ADC is negatively regulated by mechanisms requiring either cAMP and cAMP receptor protein (CRP) or putrescine. A 3,236 base pair (bp) BalI-AccI restriction fragment derived from plasmid pKA5, which contains a 7.5 kilobase (kb) E. coli genomic fragment in pBR322, was subcloned into pGEM-3Z to produce plasmids pRM15 and pRM59. Both pRM15 and pRM59 overexpress ADC and the DNA sequence of the BalI-AccI fragment in each plasmid was determined. A 2,119 bp restriction fragment containing 730 bp 5’ to speA, the speA promoter, and 1,389 bp (463 amino acids) of the 5’-end of speA was used to construct transcriptional (pRM161 and pRM162) and translational (pRM65) speA-lacZ fusion plasmids. The presence of the predicted 160,000 and 157,000 dalton ADC

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Veterinary Medical Sciences

Department dc:contributor.department

Veterinary Medical Sciences

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1990

Author dc:creator

• Moore, Robert C.

Chair dc:contributor.committeechair

• Boyle, Stephen M.

Committee members dc:contributor.committeemember

• Dean, Dennis R.
• Johnson, John L.
• Lacy, George H.
• Larson, Timothy J.
• Sriranganathan, Nammalwar

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-09202005-090951

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/39408