Scandium, Yttrium and the Lanthanide Metals

2016 ◽  
pp. 225-324
Keyword(s):  
Lanthanide Metals

scholarly journals A Dy(III) Fluorescent Single-Molecule Magnet Based on a Rhodamine 6G Ligand

Inorganics ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 51
Author(s):  
Lin Miao ◽  
Mei-Jiao Liu ◽  
Man-Man Ding ◽  
Yi-Quan Zhang ◽  
Hui-Zhong Kou
Keyword(s):  
Magnetic Properties ◽  
Single Molecule ◽  
Magnetic Relaxation ◽  
Rhodamine 6G ◽  
Bond Angle ◽  
Magnetic Measurements ◽  
Single Molecule Magnet ◽  
Lanthanide Metals ◽  
Process Studies ◽  
Dual Functions

The complexes of lanthanide metals, especially dysprosium, can generally exhibit excellent magnetic properties. By means of modifying ligands, dual functions or even multi-functions can be achieved. Here, we synthesized an eight-coordinate Dy(III) complex 1, [Dy(HL-o)2(MeOH)2](ClO4)3·4.5MeOH, which is single-molecule magnet (SMM), and the introduction of the rhodamine 6G chromophore in the ring-opened ligand HL-o realizes ligand-centered fluorescence in addition to SMM. Magnetic measurements and ab initio calculations indicate that the magnetic relaxation for complex 1 should be due to the Raman relaxation process. Studies on magneto-structural correlationship of the rhodamine salicylaldehyde hydrazone Dy(III) complexes show that the calculated energy of the first Kramers Doublet (EKD1) is basically related to the Ophenoxy-Dy-Ophenoxy bond angle, i.e., the larger Ophenoxy-Dy-Ophenoxy bond angle corresponds to a larger EKD1.

Potentiometry of the Dioxa–Triaza Macrocyclic Complexes as Receptors for First-Row Transition and Lanthanide Metals

1996 ◽  
Vol 53 (2) ◽  
pp. 180-187 ◽  
Author(s):  
Ki-Young Choi ◽  
Yong-Ill Lee ◽  
Hee-Sup Kil ◽  
Dong-Won Kim ◽  
Yong-Soon Chung ◽  
...  
Keyword(s):  
Macrocyclic Complexes ◽  
Lanthanide Metals

scholarly journals A Mutagenic Screen Identifies a TonB-Dependent Receptor Required for the Lanthanide Metal Switch in the Type I Methanotroph “Methylotuvimicrobium buryatense” 5GB1C

2019 ◽  
Vol 201 (15) ◽  
Author(s):  
Joseph D. Groom ◽  
Stephanie M. Ford ◽  
Mitchell W. Pesesky ◽  
Mary E. Lidstrom
Keyword(s):  
Metal Ion ◽  
Single Gene ◽  
Methanol Dehydrogenase ◽  
Chemical Mutagenesis ◽  
Type I ◽  
Biological Interactions ◽  
Atmospheric Methane ◽  
Metal Transporters ◽  
Lanthanide Metals ◽  
Lanthanide Metal

ABSTRACTSeveral of the metabolic enzymes in methanotrophic bacteria rely on metals for both their expression and their catalysis. The MxaFI methanol dehydrogenase enzyme complex uses calcium as a cofactor to oxidize methanol, while the alternative methanol dehydrogenase XoxF uses lanthanide metals such as lanthanum and cerium for the same function. Lanthanide metals, abundant in the earth’s crust, strongly repress the transcription ofmxaFyet activate the transcription ofxoxF. This regulatory program, called the “lanthanide switch,” is central to methylotrophic metabolism, but only some of its components are known. To uncover additional components of the lanthanide switch, we developed a chemical mutagenesis system in the type I gammaproteobacterial methanotroph “Methylotuvimicrobium buryatense” 5GB1C and designed a selection system for mutants unable to repress themxaFpromoter in the presence of lanthanum. Whole-genome resequencing for multiple lanthanide switch mutants identified several unique point mutations in a single gene encoding a TonB-dependent receptor, which we have named LanA. The LanA TonB-dependent receptor is absolutely required for the lanthanide switch and controls the expression of a small set of genes. While mutation of thelanAgene does not affect the amount of cell-associated lanthanum, it is essential for growth in the absence of the MxaF methanol dehydrogenase, suggesting that LanA is involved in lanthanum uptake to supply the XoxF methanol dehydrogenase with its critical metal ion cofactor. The discovery of this novel component of the lanthanide regulatory system highlights the complexity of this circuit and suggests that further components are likely involved.IMPORTANCELanthanide metals, or rare earth elements, are abundant in nature and used heavily in technological devices. Biological interactions with lanthanides are just beginning to be unraveled. Until very recently, microbial mechanisms of lanthanide metal interaction and uptake were unknown. The TonB-dependent receptor LanA is the first lanthanum receptor identified in a methanotroph. Sequence homology searches with known metal transporters and regulators could not be used to identify LanA or other lanthanide metal switch components, and this method for mutagenesis and selection was required to identify the receptor. This work advances the knowledge of microbe-metal interactions in environmental niches that impact atmospheric methane levels and are thus relevant to climate change.

Stepwise and reversible cleavage of the carbon-oxygen double bond of diaryl ketones by lanthanide metals

1992 ◽  
Vol 11 (7) ◽  
pp. 2711-2714 ◽  
Author(s):  
Zhaomin Hou ◽  
Hiroshi Yamazaki ◽  
Yuzo Fujiwara ◽  
Hiroshi Taniguchi
Keyword(s):  
Double Bond ◽  
Lanthanide Metals
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