7OQX

Crystal structure of a psychrophilic CCA-adding enzyme in complex with CMPcPP

Summary for 7OQX

• Entry DOI: 10.2210/pdb7oqx/pdb
• Related: 6QXN 6QY6
• Descriptor: CCA-adding enzyme, 5'-O-[(S)-hydroxy{[(S)-hydroxy(phosphonooxy)phosphoryl]methyl}phosphoryl]cytidine, PHOSPHATE ION, ... (6 entities in total)
• Functional Keywords: trna maturation, trna nucleotidyltransferase, psychrophilic enzyme, rna binding protein
• Biological source: Planococcus halocryophilus
• Total number of polymer chains: 1
• Total formula weight: 49792.88

Authors

Rollet, K.,de Wijn, R.,Bluhm, A.,Hennig, O.,Betat, H.,Moerl, M.,Lorber, B.,Sauter, C. (deposition date: 2021-06-04, release date: 2021-11-03, Last modification date: 2024-01-31)

Primary citation

de Wijn, R.,Rollet, K.,Ernst, F.G.M.,Wellner, K.,Betat, H.,Morl, M.,Sauter, C.
CCA-addition in the cold: Structural characterization of the psychrophilic CCA-adding enzyme from the permafrost bacterium Planococcus halocryophilus .
Comput Struct Biotechnol J, 19:5845-5855, 2021

PubMed Abstract: CCA-adding enzymes are highly specific RNA polymerases that add and maintain the sequence C-C-A at tRNA 3'-ends. Recently, we could reveal that cold adaptation of such a polymerase is not only achieved at the expense of enzyme stability, but also at the cost of polymerization fidelity. Enzymes from psychrophilic organisms usually show an increased structural flexibility to enable catalysis at low temperatures. Here, polymerases face a dilemma, as there is a discrepancy between the need for a tightly controlled flexibility during polymerization and an increased flexibility as strategy for cold adaptation. Based on structural and biochemical analyses, we contribute to clarify the cold adaptation strategy of the psychrophilic CCA-adding enzyme from , a gram-positive bacterium thriving in the arctic permafrost at low temperatures down to -15 °C. A comparison with the closely related enzyme from the thermophilic bacterium reveals several features of cold adaptation - a significantly reduced amount of alpha-helical elements in the C-terminal tRNA-binding region and a structural adaptation in one of the highly conserved catalytic core motifs located in the N-terminal catalytic core of the enzyme.

PubMed: 34765099
DOI: 10.1016/j.csbj.2021.10.018

Experimental method

X-RAY DIFFRACTION (2.2 Å)