Extended region of nodulation genes in Rhizobium meliloti 1021. II. Nucleotide sequence, transcription start sites and protein products

Journal Article · Thu Oct 01 04:00:00 EDT 1987 · Genetics; (United States)

OSTI ID:5303278

Fisher, R F; Swanson, J A; Mulligan, J T; Long, S R

The authors have established the DNA sequence and analyzed the transcription and translation products of a series of putative nodulation (nod) genes in Rhizobium meliloti strain 1021. Four loci have been designated nodF, nodE, nodG and nodH. The correlation of transposon insertion positions with phenotypes and open reading frames was confirmed by sequencing the insertion junctions of the transposons. The protein products of these nod genes were visualized by in vitro expression of cloned DNA segments in a R. meliloti transcription-translation system. In addition, the sequence for nodG was substantiated by creating translational fusions in all three reading frames at several points in the sequence; the resulting fusions were expressed in vitro in both E. coli and R. meliloti transcription-translation systems. A DNA segment bearing several open reading frames downstream of nodG corresponds to the putative nod gene mutated in strain nod-216. The transcription start sites of nodF and nodH were mapped by primer extension of RNA from cells induced with the plant flavone, luteolin. Initiation of transcription occurs approximately 25 bp downstream from the conserved sequence designated the nod box, suggesting that this conserved sequence acts as an upstream regulator of inducible nod gene expression. Its distance from the transcription start site is more suggestive of an activator binding site rather than an RNA polymerase binding site.

• Research Organization: Stanford Univ., CA
• OSTI ID: 5303278
• Journal Information: Genetics; (United States), Journal Name: Genetics; (United States) Vol. 117:2; ISSN GENTA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AUTORADIOGRAPHY
BACTERIA
BACTERIOPHAGES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOSYNTHESIS
CELL CONSTITUENTS
CLONING
DAYS LIVING RADIOISOTOPES
DNA SEQUENCING
DNA-CLONING
ENZYMES
GENES
ISOTOPES
LIGHT NUCLEI
MICROORGANISMS
NUCLEI
NUCLEOTIDYLTRANSFERASES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
PARASITES
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PHOSPHORUS-GROUP TRANSFERASES
PLASMIDS
POLYMERASES
PROTEINS
RADIOISOTOPES
RHIZOBIUM
RNA POLYMERASES
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
TRANSCRIPTION
TRANSFERASES
VIRUSES