The broad bean gene VfNOD32 encodes a nodulin with sequence similarities to chitinases that is homologous to (alpha/beta)8-barrel-type seed proteins.
Plant Physiol
; 110(1): 147-54, 1996 Jan.
Article
en En
| MEDLINE
| ID: mdl-8587978
Nodulin gene transcripts isolated from a broad bean (Vicia faba L.) root nodule cDNA library and designated VfNOD32 are detectable in the nitrogen-fixing zone III of nodules and in much smaller amounts in flowers. In nodules, these transcripts are detectable for the first time 7 d after inoculation, at least 1 d before leghemoglobin gene transcription starts. Two putative full-length cDNAs representing different transcript sequences of 92.5% identity were sequenced. The corresponding broad bean genes were termed VfNOD32-A1 and VfNOD32-A2, and the encoded proteins were termed Nvf32-A1 and Nvf32-A2. The derived amino acid sequences of the Nvf32 proteins are highly homologous to the Vicia narbonensis (alpha/beta)8-barrel seed protein narbonin. Considering this homology, Nvf32 is assumed to have a similar structure consisting of beta-sheets forming a central barrel surrounded by alpha-helices. The two Nvf32 sequences also contain two conserved amino acid motifs that are characteristic of class-III chitinases. Several amino acids demonstrated to be essential for chitinase activity are conserved in both regions, whereas one essential glutamic acid was changed to glycine in the Nvf32-A1 isoform but not in the Nvf32-A2 isoform.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Plantas
/
Plantas Medicinales
/
Genes de Plantas
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Fabaceae
/
Proteínas de la Membrana
Idioma:
En
Revista:
Plant Physiol
Año:
1996
Tipo del documento:
Article
País de afiliación:
Alemania
Pais de publicación:
Estados Unidos