Sinorhizobium meliloti YrbA binds divalent metal cations using two conserved histidines
Thomas Roret1,2, Geneviève Alloing3, Jean-Michel Girardet1
1Université de Lorraine, INRAE, IAM, Nancy, France.
Bioscience Reports
|September 24, 2020
Summary
Sinorhizobium meliloti
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Sinorhizobium meliloti forms symbiotic nodules with legumes.
- The roles of BolA-like proteins (BolA and YrbA) in S. meliloti are unknown.
- BolA proteins and glutaredoxins (Grxs) often regulate iron homeostasis and iron-sulfur (Fe-S) protein maturation.
Purpose of the Study:
- To investigate the structure-function relationship of SmYrbA.
- To determine the role of SmYrbA in metal ion coordination and heterodimer formation.
- To elucidate the function of BolA-like proteins in S. meliloti iron homeostasis and symbiosis.
Main Methods:
- Structure-function analysis of SmYrbA.
- Metal ion coordination assays.
- Heterodimerization studies with SmGrx2.
- Analysis of metal tolerance in S. meliloti mutant strains.
- Assessment of nodulation phenotypes in Medicago truncatula.
Main Results:
- SmYrbA coordinates various divalent metal ions (Fe2+, Co2+, Ni2+, Cu2+, Zn2+) via His32 and His67 residues.
- SmYrbA forms heterodimers with SmGrx2.
- YrbA is involved in regulating iron homeostasis in S. meliloti.
- The yrbA bolA mutant shows mild nodulation defects, distinct from grx2 mutant phenotypes.
Conclusions:
- SmYrbA plays a role in metal ion binding and potentially Fe-S cluster coordination.
- YrbA contributes to iron homeostasis regulation in S. meliloti.
- BolA-like proteins have functions in bacterial symbiosis that may be independent of SmGrx2.
More Related Videos
07:26Metal-Limited Growth of Neisseria gonorrhoeae for Characterization of Metal-Responsive Genes and Metal Acquisition from Host Ligands
Published on: March 4, 2020
5.9K
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
9.6K
Related Concept Videos
02:51Metal-Ligand Bonds
23.2K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
23.2K
02:34Structural Isomerism
21.0K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
21.0K
01:03Single-Strand DNA Binding Proteins
16.2K
For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes...
16.2K
01:19Complexation Equilibria: The Chelate Effect
959
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
959
02:42Valence Bond Theory
10.5K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
10.5K
01:30Bacterial Phylum Actinobacteria
388
Coryneform bacteria are gram-positive, aerobic, nonmotile rods that exhibit irregular, club-shaped, or V-shaped arrangements. Their V-shape results from snapping division, where the inner cell wall layer forms the cross-wall, while the outer layer remains intact until it ruptures on one side, causing the daughter cells to bend away.The primary genera are Corynebacterium and Arthrobacter. Corynebacterium includes diverse species, ranging from saprophytes to pathogens like Corynebacterium...
388