scholarly journals Histidine residues of zinc ligands in β-lactamase II

1978 ◽  
Vol 175 (2) ◽  
pp. 441-447 ◽  
Author(s):  
G S Baldwin ◽  
A Galdes ◽  
H A O Hill ◽  
B E Smith ◽  
S G Waley ◽  
...  

1. The Zn(II)-requiring beta-lactamase from Bacillus cereus 569/H/9, which has two zinc-binding sites, was examined by 270 MHz 1H n.m.r. spectroscopy. Resonances were assigned to five histidine residues. 2. Resonances attributed to three of the histidine residues in the apoenzyme shift on the addition of one equivalent of Zn(II). 3. Although these three histidine residues are free to titrate in the apoenzyme, none of them titrates over the pH range 6.0–9.0 in the mono-zinc enzyme. 4. The ability of the C-2 protons of these three histidine residues to exchange with solvent (2H2O) is markedly decreased on Zn(II) binding. 5. It is proposed that these three histidine residues act as zinc ligands at the tighter zinc-binding site. 6. Resonances attributed to a fourth histidine residue shift on addition of further zinc to the mono-zinc enzyme. It is proposed that this histidine residue acts as a Zn(II) ligand at the second zinc-binding site.

1979 ◽  
Vol 179 (3) ◽  
pp. 459-463 ◽  
Author(s):  
G S Baldwin ◽  
S G Waley ◽  
E P Abraham

1. Four histidine-containing peptides have been isolated from a tryptic digest of the Zn2+-requiring beta-lactamase II from Bacillus cereus. One of these peptides probably contains two histidine residues. 2. The presence of one equivalent of Zn2+ substantially decreases the rate of exchange of the C-2 proton in at least two and probably three of the histidine residues of these peptides for solvent 3H. 3. It is concluded that peptides containing at least two of the three histidine residues acting as Zn2+ ligands at the tighter Zn2+-binding site of beta-lactamase II have been identified.


2013 ◽  
Vol 21 (11) ◽  
pp. 3138-3146 ◽  
Author(s):  
Pei W. Thomas ◽  
Timothy Spicer ◽  
Michael Cammarata ◽  
Jennifer S. Brodbelt ◽  
Peter Hodder ◽  
...  

2019 ◽  
Vol 15 (3) ◽  
pp. 205-215 ◽  
Author(s):  
Renxiang Yan ◽  
Xiaofeng Wang ◽  
Yarong Tian ◽  
Jing Xu ◽  
Xiaoli Xu ◽  
...  

The zinc (Zn2+) cofactor has been proven to be involved in numerous biological mechanisms and the zinc-binding site is recognized as one of the most important post-translation modifications in proteins.


Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 966
Author(s):  
Sam M. Ireland ◽  
Andrew C. R. Martin

Background: Zinc binding proteins make up a significant proportion of the proteomes of most organisms and, within those proteins, zinc performs rôles in catalysis and structure stabilisation. Identifying the ability to bind zinc in a novel protein can offer insights into its functions and the mechanism by which it carries out those functions. Computational means of doing so are faster than spectroscopic means, allowing for searching at much greater speeds and scales, and thereby guiding complimentary experimental approaches. Typically, computational models of zinc binding predict zinc binding for individual residues rather than as a single binding site, and typically do not distinguish between different classes of binding site—missing crucial properties indicative of zinc binding. Methods: Previously, we created ZincBindDB, a continuously updated database of known zinc binding sites, categorised by family (the set of liganding residues). Here, we use this dataset to create ZincBindPredict, a set of machine learning methods to predict the most common zinc binding site families for both structure and sequence. Results: The models all achieve an MCC ≥ 0.88, recall ≥ 0.93 and precision ≥ 0.91 for the structural models (mean MCC = 0.97), while the sequence models have MCC ≥ 0.64, recall ≥ 0.80 and precision ≥ 0.83 (mean MCC = 0.87), with the models for binding sites containing four liganding residues performing much better than this. Conclusions: The predictors outperform competing zinc binding site predictors and are available online via a web interface and a GraphQL API.


2018 ◽  
Vol 116 (2) ◽  
pp. 528-533 ◽  
Author(s):  
Ivan B. Lomakin ◽  
Sergey E. Dmitriev ◽  
Thomas A. Steitz

The density-regulated protein (DENR) and the malignant T cell-amplified sequence 1 (MCT-1/MCTS1) oncoprotein support noncanonical translation initiation, promote translation reinitiation on a specific set of mRNAs with short upstream reading frames, and regulate ribosome recycling. DENR and MCT-1 form a heterodimer, which binds to the ribosome. We determined the crystal structure of the heterodimer formed by human MCT-1 and the N-terminal domain of DENR at 2.0-Å resolution. The structure of the heterodimer reveals atomic details of the mechanism of DENR and MCT-1 interaction. Four conserved cysteine residues of DENR (C34, C37, C44, C53) form a classical tetrahedral zinc ion-binding site, which preserves the structure of the DENR’s MCT-1–binding interface that is essential for the dimerization. Substitution of all four cysteines by alanine abolished a heterodimer formation. Our findings elucidate further the mechanism of regulation of DENR-MCT-1 activities in unconventional translation initiation, reinitiation, and recycling.


1998 ◽  
Vol 76 (7) ◽  
pp. 1027-1032 ◽  
Author(s):  
Silvia Álvarez-Santos ◽  
Àngels González-Lafont ◽  
José M Lluch

The hydrogen bond network influence on the carbonic anhydrase II (CAII) zinc binding site has been studied theoretically by using the semiempirical AM1 method. To this aim, quantum mechanical reduced models of wild-type CAII and several CAII variants have been constructed. We have shown that, when a direct metal ligand donates a hydrogen bond to an indirect metal ligand, the first-shell residues enhance their electrostatic interaction with the zinc cation. Thus, the hydrogen-bond network is able to modulate the zinc binding affinity and the zinc-water pKa.Key words: hydrogen bond network, carbonic anhydrase II, Zn2+ metalloenzyme ligands.


2000 ◽  
Vol 276 (13) ◽  
pp. 10110-10118 ◽  
Author(s):  
Anders A. Jensen ◽  
Paul O. Sheppard ◽  
Liselotte B. Jensen ◽  
Patrick J. O'Hara ◽  
Hans Bräuner-Osborne

Sign in / Sign up

Export Citation Format

Share Document