literature

Immune Evasion of SARS-CoV-2 Emerging Variants: What Have We Learnt So Far?

PMID: 34206453 2021 Viruses

Introduction: All three sublineages of B.1.617 display P681R adjacent to the furin cleavage site and have enhanced S cleavage by furin, which is hypothesized to be enhancing transmissibility and pathogenicity.

Introduction: It is characterized by spike mutations T19R, G142D, Delta157-158, L452R, T478K, D614G, P681R, and D950N (Figure 3).

Introduction: The other two sublineages have a similar mutational profile: B.1.617.1 is defined by the spike amino acid changes G142D, E154K, L452R,

PMID: 34207378 2021 Viruses

Introduction: It carries Spike mutations including E484K, N501Y, D614G, P681H/R, and V1176F.

Insilico study on the effect of SARS-CoV-2 RBD hotspot mutants' interaction with ACE2 to understand the binding affinity and stability.

PMID: 34217923 2021 Virology

Introduction: The lineage is B.1.617.2 (Delta) with mutations, L452R, T478K, D614G and P681R in the S protein.

Evolutionary insights into the furin cleavage sites of SARS-CoV-2 variants from humans and animals.

PMID: 34258664 2021 Archives of virology

Result: On the other hand, 13 FCS mutations, namely, S680P, S680F, P681H, P681R, P681S, P681L, R682W, Table: P681R

Discussion: Deep analysis of SARS-CoV-2 S protein sequences revealed multiple substitutions, including S680P/F, P681H/R/S/L, R682G/Q/W, R683G/P, A684E/S/T/V, S686R, V687I, and A688S/V (Table 1).

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

PMID: 34260088 2021 Journal of medical virology

Abstract: This variant has 13 amino acid changes, three in its spike protein, which are currently of particular concern: E484Q, L452R, and P681R.

Trajectory of Growth of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Variants in Houston, Texas, January through May 2021, Based on 12,476 Genome Sequences.

PMID: 34303698 2021 The American journal of pathology

Result: These two variants are characterized by a core group of amino acid replacements in spike protein: L452R, T478K or E484Q, D614G, and P681R (Figure 6).

Conformational Variability Correlation Prediction of Transmissibility and Neutralization Escape Ability for Multiple Mutation SARS-CoV-2 Strains using SSSCPreds.

PMID: 34337269 2021 ACS omega

Introduction: The main protein substitutions are L452R, E484Q (or T478K), D614G, and P681R.

Result: B.1.1.7 and B.1.617.2 strains have the P681H/R mutation sites at the furin cleavage site of SARS-CoV-2.

Result: The sequence flexibility/rigidity map patterns of the P681H/R mutation sites are more flexible than that of the wild-type strain.

Modelling conformational state dynamics and its role on infection for SARS-CoV-2 Spike protein variants.

PMID: 34351895 2021 PLoS computational biology

Result: For example, the Indian variant B.1.617.2 (also known as Delta), contains a core number of mutations in Spike (G142D, E154K, L452R, E484Q, D614G, P681R, Q1071H) but also additional sub-strain variations (T95I, H1101D or V382L).

Neutralizing Activity of Sera from Sputnik V-Vaccinated People against Variants of Concern (VOC: B.1.1.7, B.1.351, P.1, B.1.617.2, B.1.617.3) and Moscow Endemic SARS-CoV-2 Variants.

PMID: 34358195 2021 Vaccines

Method: Determination of NtAb titers was evaluated using the following SARS-CoV-2 variants: B.1.1.1 (PMVL-1, S: D614G; hCoV-19/Russia/Moscow_PMVL-1/2020), B.1.1.7 (hCoV-19/Netherlands/NoordHolland_20432/2020, VOC 202012/01), B.1.351 (hCoV-19/Russia/SPE-RII-27029S/2021), B.1.1.141 (PMVL-31, S: M153T, T385I, D614G; hCoV-19/Russia/MOW-PMVL-31/2020), B.1.1.317 (PMVL-43, S: D138Y, S477N, A522S, D614G, Q675R, A845S; hCoV-19/Russia/MOW-PMVL-43/2021), B.1.1.28/P.1 (hCoV-19/Netherlands/NoordHolland_10915/2021), B.1.617.2 (T19R

Spike protein cleavage-activation mediated by the SARS-CoV-2 P681R mutation: a case-study from its first appearance in variant of interest (VOI) A.23.1 identified in Uganda.

PMID: 34361977 2021 Microorganisms

8Discussion: P681H is one of the mutations in the VIC alpha, while P681R is one of the mutations in the lineage A.23.1, which is identified as a ""variant under monitoring"" (, Accessed on 14 June 2021)."

Discussion: Another significant mutation, P681R, in the furin cleavage site resulted in enhancement of the basicity of the poly-basic stretch, and the likely facilitation of additional contacts with furin for S1-S2 cleavage.

Discussion: On the other hand, the B.1.617.1 lineage possessing common signature mutations L452R, E484Q and P681R in the spike protein could be linked to the surge of cases in February 2021 in eastern Maharashtra.