caa a22 4500 605537402 CHVBK 20210128100857.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s10517-015-2860-6 doi (NATIONALLICENCE)springer-10.1007/s10517-015-2860-6 Abnormal Morphological Vesicles in Influenza a Virus Exposed to Acid pH [Elektronische Daten] [O. Zhirnov, A. Manykin] Vesicles on the virion surface, which continued the lipoprotein membrane but had no spikes of virus glycoproteins hemagglutinin (HA) and neuraminidase (NA), were detected. These vesicles and virus particles were 18±7 and 103±12 nm in diameter, respectively, and, as a rule, one vesicle was found per virion. The locus of the external protrusion in the virion presumably corresponded to the site of virus budding during assembly in infected cell free from HA and NA spikes outside and M1 matrix protein inside, but enriched with ionic channel protein M2. Particles with vesicles constituted ~3-10% of the virus population produced in MDCK-H culture and containing uncleaved HA0 hemagglutinin. The content of vesicular virions increased slightly after trypsin cleavage HA0→HA1+HA2 and reached 10-15%. Exposure of the virus in acid medium (pH 4.3) led to a drastic increase of vesicular virions - to 60-80% for HA0 and HA1+HA2 virus. This was paralleled by changes in contrast permeability (for phosphotungstic acid). HA0 virions remained contrast-impermeable, while HA1+HA2 particles let the contrast in through the vesicles detected on the surface and were rapidly destroyed after incubation in acid medium. Hence, cleavage of the surface glycoprotein HA0 into HA1 and HA2 stimulated the acid-dependent permeability of the lipid membrane and led to attenuation of the ribonucleoprotein and protein matrix M1 contacts inside the virion. Springer Science+Business Media New York, 2015 influenza virus nationallicence structure nationallicence lipid membrane nationallicence acid pH nationallicence Zhirnov O. D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences, Moscow, Russia aut Manykin A. D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences, Moscow, Russia aut Bulletin of Experimental Biology and Medicine Springer US; http://www.springer-ny.com 158/6(2015-04-01), 776-780 0007-4888 158:6<776 2015 158 10517 https://doi.org/10.1007/s10517-015-2860-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10517-015-2860-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zhirnov O. D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences, Moscow, Russia aut NATIONALLICENCE 700 1- Manykin A. D. I. Ivanovsky Research Institute of Virology, Russian Academy of Medical Sciences, Moscow, Russia aut NATIONALLICENCE 773 0- Bulletin of Experimental Biology and Medicine Springer US; http://www.springer-ny.com 158/6(2015-04-01), 776-780 0007-4888 158:6<776 2015 158 10517