7yr2
SARS-CoV-2 BA.2.75 S Trimer in complex with ACE2(state1)SARS-CoV-2 BA.2.75 S Trimer in complex with ACE2(state1)
Structural highlights
FunctionACE2_HUMAN Carboxypeptidase which converts angiotensin I to angiotensin 1-9, a peptide of unknown function, and angiotensin II to angiotensin 1-7, a vasodilator. Also able to hydrolyze apelin-13 and dynorphin-13 with high efficiency. May be an important regulator of heart function. In case of human coronaviruses SARS and HCoV-NL63 infections, serve as functional receptor for the spike glycoprotein of both coronaviruses.[1] [2] [3] Publication Abstract from PubMedRecently emerged SARS-CoV-2 Omicron subvariant, BA.2.75, displayed a growth advantage over circulating BA.2.38, BA.2.76, and BA.5 in India. However, the underlying mechanisms for enhanced infectivity, especially compared with BA.5, remain unclear. Here, we show that BA.2.75 exhibits substantially higher affinity for host receptor angiotensin-converting enzyme 2 (ACE2) than BA.5 and other variants. Structural analyses of BA.2.75 spike shows its decreased thermostability and increased frequency of the receptor binding domain (RBD) in the "up" conformation under acidic conditions, suggesting enhanced low-pH-endosomal cell entry. Relative to BA.4/BA.5, BA.2.75 exhibits reduced evasion of humoral immunity from BA.1/BA.2 breakthrough-infection convalescent plasma but greater evasion of Delta breakthrough-infection convalescent plasma. BA.5 breakthrough-infection plasma also exhibits weaker neutralization against BA.2.75 than BA.5, mainly due to BA.2.75's distinct neutralizing antibody (NAb) escape pattern. Antibody therapeutics Evusheld and Bebtelovimab remain effective against BA.2.75. These results suggest BA.2.75 may prevail after BA.4/BA.5, and its increased receptor-binding capability could support further immune-evasive mutations. Characterization of the enhanced infectivity and antibody evasion of Omicron BA.2.75.,Cao Y, Song W, Wang L, Liu P, Yue C, Jian F, Yu Y, Yisimayi A, Wang P, Wang Y, Zhu Q, Deng J, Fu W, Yu L, Zhang N, Wang J, Xiao T, An R, Wang J, Liu L, Yang S, Niu X, Gu Q, Shao F, Hao X, Meng B, Gupta RK, Jin R, Wang Y, Xie XS, Wang X Cell Host Microbe. 2022 Nov 9;30(11):1527-1539.e5. doi: , 10.1016/j.chom.2022.09.018. Epub 2022 Oct 4. PMID:36270286[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
|