Any feedback?
Please rate this page
(literature.php)
(0/150)

BRENDA support

Literature summary extracted from

  • Saramago, M.; Robledo, M.; Matos, R.; Jimenez-Zurdo, J.; Arraiano, C.
    Sinorhizobium meliloti RNase III catalytic features and impact on symbiosis (2018), Front. Genet., 9, 350 .
    View publication on PubMedView publication on EuropePMC

Cloned(Commentary)

EC Number Cloned (Comment) Organism
3.1.26.3 gene rnc, DNA and amino acid sequence determination and analysis, sequence comparisons and phylogenetic tree, recombinant expression of His-tagged wild-type and mutant enzymes in Escherichia coli strain BL21(DE3) recArnc105. This strain, carrying an RNase III mutation, is used because it blocks the autoregulation of SmRNase III by the endogenous Escherichia coli homolog, resulting in a higher yield of the enzyme upon overexpression Sinorhizobium meliloti

Protein Variants

EC Number Protein Variants Comment Organism
3.1.26.3 E125A site-directed mutagenesis, the mutation does not compromise wild-type enzyme SmRNase III dimerization ability Sinorhizobium meliloti
3.1.26.3 E125Q site-directed mutagenesis, mutation does not compromise wild-type enzyme SmRNase III dimerization ability Sinorhizobium meliloti
3.1.26.3 additional information an enzyme deletion mutant SmDELTArnc shows a symbiotic phenotype. Plants inoculated with the wild-type and complemented strains developed significantly longer shoots than those inoculated with the mutant bacteria, SmDELTArnc or SmDELTArnc (pSRK), which are similar to those of the control mock-treated plants Sinorhizobium meliloti

Inhibitors

EC Number Inhibitors Comment Organism Structure
3.1.26.3 Mn2+ activates at 0.1-50 mM, inhibitory at 100 mM Sinorhizobium meliloti

Metals/Ions

EC Number Metals/Ions Comment Organism Structure
3.1.26.3 Mg2+ activates, required Sinorhizobium meliloti
3.1.26.3 Mn2+ activates, required, best metal ion at 0.1-50 mM, inhibitory at 100 mM Sinorhizobium meliloti
3.1.26.3 additional information Ca2+ does not likely support enzyme activity. Strictly metal cofactor-dependent activity of SmRNase III on the model R1.1 substrate Sinorhizobium meliloti

Natural Substrates/ Products (Substrates)

EC Number Natural Substrates Organism Comment (Nat. Sub.) Natural Products Comment (Nat. Pro.) Rev. Reac.
3.1.26.3 additional information Sinorhizobium meliloti enzyme SmRNase III is double-strand specific and exhibits different preference for endogenous RNA substrates ?
-
 ?

Organism

EC Number Organism UniProt Comment Textmining
3.1.26.3 Sinorhizobium meliloti Q92R47 i.e. Ensifer meliloti or Sinorhizobium meliloti
-

Purification (Commentary)

EC Number Purification (Comment) Organism
3.1.26.3 recombinant His-tagged wild-type and mutant enzymes from Escherichia coli strain BL21(DE3)recArnc105 by nickel affinity chromatography and gel filtration Sinorhizobium meliloti

Substrates and Products (Substrate)

EC Number Substrates Comment Substrates Organism Products Comment (Products) Rev. Reac.
3.1.26.3 additional information enzyme SmRNase III is double-strand specific and exhibits different preference for endogenous RNA substrates Sinorhizobium meliloti ?
-
 ?
3.1.26.3 R1.1 RNA + H2O R1.1 is a structured 60 nucleotides (nt)-long RNA molecule containing an asymmetric (4 nt/5 nt) internal loop, and it comes from the phage T7 early region between genes 1.0 and 1.1. This RNA contains an RNase III primary cleavage site (a) that is recognized in vivo and in vitro, and a secondary site (b) that is cleaved only in vitro. RNase III is known to cleave R1.1 at these two preferred sites (a and b) in a metal cofactor-dependent manner. Strictly metal cofactor-dependent activity of SmRNase III on the model R1.1 substrate Sinorhizobium meliloti ?
-
 ?

Synonyms

EC Number Synonyms Comment Organism
3.1.26.3 RNase III
-
 Sinorhizobium meliloti
3.1.26.3 RNase III-like protein
-
 Sinorhizobium meliloti
3.1.26.3 rnc
-
 Sinorhizobium meliloti
3.1.26.3 SmRNase III
-
 Sinorhizobium meliloti

Temperature Optimum [°C]

EC Number Temperature Optimum [°C] Temperature Optimum Maximum [°C] Comment Organism
3.1.26.3 37
-
 assay at Sinorhizobium meliloti

pH Optimum

EC Number pH Optimum Minimum pH Optimum Maximum Comment Organism
3.1.26.3 8
-
 assay at Sinorhizobium meliloti

General Information

EC Number General Information Comment Organism
3.1.26.3 evolution members of the ribonuclease (RNase) III family of enzymes are metal-dependent double-strand specific endoribonucleases. They are ubiquitously found and eukaryotic RNase III-like enzymes include Dicer and Drosha, involved in RNA processing and RNA interference. SmRNase III is a typical double-strand specific endoribonuclease, but with a minimal substrate length requirement different from that of its enterobacterial orthologue Sinorhizobium meliloti
3.1.26.3 malfunction SmRNase III loss-of-function neither compromises viability nor alters morphology of Sinorhizobium meliloti cells, but influences growth, nodulation kinetics, the onset of nitrogen fixation and the overall symbiotic efficiency of this bacterium on the roots of its legume host, alfalfa, which ultimately affects plant growth. Appearance of pink nodules. Symbiotic phenotype of the SmDELTArnc mutant Sinorhizobium meliloti
3.1.26.3 additional information probably a major role of the ultraconserved E125 amino acid in the metal-dependent catalysis mediated by enzyme SmRNase III Sinorhizobium meliloti
3.1.26.3 physiological function SmRNase III degrades endogenous RNA substrates of diverse biogenesis with different efficiency, and is involved in the maturation of the 23S rRNA. Impact of SmRNase III on nodulation and symbiotic nitrogen fixation in plants. Enzyme SmRNase III influences free-living growth and symbiotic performance of Sinorhizobium meliloti on alfalfa roots Sinorhizobium meliloti