scholarly journals SARS-CoV-2 B.1.617 Indian variants: are electrostatic potential changes responsible for a higher transmission rate?

2021 ◽  
Author(s):  
Stefano Pascarella ◽  
Massimo Ciccozzi ◽  
Davide Zella ◽  
Martina Bianchi ◽  
Francesca Benedetti ◽  
...  

Lineage B.1.617+, also known as G/452R.V3, is a recently described SARS-CoV-2 variant under investigation (VUI) firstly identified in October 2020 in India. As of May 2021, three sublineages labelled as B.1.617.1, B.1.617.2 and B.1.617.3 have been already identified, and their potential impact on the current pandemic is being studied. This variant has 13 amino acid changes, three in its spike protein, which are currently of particular concern: E484Q, L452R and P681R. Here we report a major effect of the mutations characterizing this lineage, represented by a marked alteration of the surface electrostatic potential (EP) of the Receptor Binding Domain (RBD) of the spike protein. Enhanced RBD-EP is particularly noticeable in the B.1.617.2 sublineage, which shows multiple replacements of neutral or negatively-charged amino acids with positively-charged amino acids. We here hypothesize that this EP change can favor the interaction between the B.1.617+ RBD and the negatively-charged ACE2 thus conferring a potential increase in the virus transmission.

2009 ◽  
Vol 284 (24) ◽  
pp. 16317-16324 ◽  
Author(s):  
Sandra Mueller ◽  
Gunnar Kleinau ◽  
Mariusz W. Szkudlinski ◽  
Holger Jaeschke ◽  
Gerd Krause ◽  
...  

Bovine TSH (bTSH) has a higher affinity to the human TSHR (hTSHR) and a higher signaling activity than human TSH (hTSH). The molecular reasons for these phenomena are unknown. Distinct negatively charged residues (Glu297, Glu303, and Asp382) in the hinge region of the hTSHR are known to be important for bTSH binding and signaling. To investigate the potential relevance of these positions for differences between bTSH and hTSH in the interaction to the hTSHR, we determined bTSH- and hTSH-mediated cAMP production of several substitutions at these three hinge residues. To examine specific variations of hTSH, we also investigated the superagonistic hTSH analog TR1401 (TR1401), whose sequence differs from hTSH by four additional positively charged amino acids that are also present in bTSH. To characterize possible interactions between the acidic hTSHR positions Glu297, Glu303, or Asp382 and the additional basic residues of TR1401, we investigated TR1401 binding and signaling properties. Our data reveal increased cAMP signaling of the hTSHR using TR1401 and bTSH compared with hTSH. Whereas Asp382 seems to be important for bTSH- and TR1401-mediated but not for hTSH-mediated signaling, the substitution E297K exhibits a decreased signaling for all three TSH variants. Interestingly, bTSH and TR1401 showed only a slightly different binding pattern. These observations imply that specific residues of the hinge region are mediators of the superagonistic activity of bTSH and TR1401 in contrast to hTSH. Moreover, the simultaneous localization of binding components in the glycoprotein hormone molecule and the receptor hinge region permits important reevaluation of interacting hormone receptor domains.


2014 ◽  
Vol 95 (9) ◽  
pp. 1919-1928 ◽  
Author(s):  
Zee Hong Goh ◽  
Nur Azmina Syakirin Mohd ◽  
Soon Guan Tan ◽  
Subha Bhassu ◽  
Wen Siang Tan

White tail disease (WTD) kills prawn larvae and causes drastic losses to the freshwater prawn (Macrobrachium rosenbergii) industry. The main causative agent of WTD is Macrobrachium rosenbergii nodavirus (MrNV). The N-terminal end of the MrNV capsid protein is very rich in positively charged amino acids and is postulated to interact with RNA molecules. N-terminal and internal deletion mutagenesis revealed that the RNA-binding region is located at positions 20–29, where 80 % of amino acids are positively charged. Substitution of all these positively charged residues with alanine abolished the RNA binding. Mutants without the RNA-binding region still assembled into virus-like particles, suggesting that this region is not a part of the capsid assembly domain. This paper is, to the best of our knowledge, the first to report the specific RNA-binding region of MrNV capsid protein.


2000 ◽  
Vol 275 (14) ◽  
pp. 9986-9995 ◽  
Author(s):  
Richard J. S. Baerends ◽  
Klaas Nico Faber ◽  
Anita M. Kram ◽  
Jan A. K. W. Kiel ◽  
Ida J. van der Klei ◽  
...  

2009 ◽  
Author(s):  
Teng fei Tian ◽  
Gui zhong Liu ◽  
Xian hui Meng ◽  
Xiao qian Tan ◽  
Yong liang Liu

2020 ◽  
Vol 24 (10) ◽  
pp. 1215-1223
Author(s):  
Jesús Miguel Rivera ◽  
Margarita Rivera

The interaction of different amino acids and vacuum evaporated tetraphenyl porphyrin films was investigated by using kinetic isotherms, UV-vis spectroscopy, quartz crystal microbalance and density functional theory techniques. The adsorption process was analyzed by using pseudo-first-order and pseudo-second-order models. From these results, the adsorption order changed depending on the chemical characteristics of the porphyrin film, although most of the interactions were classified as pseudo-second-order at the films interface. From absorbance measurements, red shifts on the Soret peak positions were observed for all amino acids interacting with the metal free and the ZnTPP systems, while the position of the Soret peak barely change for the CuTPP surface, except for a slight bathocromic shift for arginine. On the other hand, the broadening of the Soret peak was more important for the ZnTPP and H2TPP surfaces, but the interaction with the CuTPP interfaces decreased the width of the peaks in all cases. In addition, a quartz crystal microbalance analysis was employed to investigate the film sensing performance during amino acid exposure. From these results, positively charged amino acids were more easily adsorbed on the films in contrast with the polar (serine) molecule. DFT calculations exhibited important deformations for H2TPP, the out-of-plane displacement of the Zn atom for ZnTPP, and hydrogen bond interactions with the CuTPP molecule. DFT also showed high binding energies for the positively charged amino acids but low binding energies for serine in agreement with experimental data. From these results, porphyrin films could be used as selective detectors for various L-amino acid molecules.


Sign in / Sign up

Export Citation Format

Share Document