AGRICULTURAL BIOLOGY, 2016, V. 51, ¹ 3, pp. 385-391 UDC 634.2:632.3:578.1:57.083 ISSN 2412-0324 (English ed. Online) (SEL’SKOKHOZYAISTVENNAYA BIOLOGIYA) ISSN 0131-6397 (Russian ed. Print) ISSN 2313-4836 (Russian ed. Online) doi: 10.15389/agrobiology.2016.3.385rus doi: 10.15389/agrobiology.2016.3.385eng IMPROVED METHOD OF PURIFICATION OF Plum pox virus AND SEROLOGICAL ANALYSIS OF THE COAT PROTEIN A.A. SHEVELEVA, N.A. NIKITIN, E.A. TRIFONOVA, A.V. ZAKUBANSKIY, S.N. CHIRKOV M.V. Lomonosov Moscow State University, Department of Virology, Biological Faculty, 1/12, Leninskie gory, Moscow, 119234 Russia, e-mail s-chirkov1@yandex.ru Acknowledgements: Supported by Russian Science Foundation, grant ¹ 14-24-00007 Received November 19, 2015 A b s t r a c t Molecular weight heterogeneity of the coat protein (CP) is commonly observed in the purified potyvirus preparations due to partial proteolysis of the N-terminal domain exposed on the surface of viral particles. <...> The N-terminal domain is the most variable part of the CP. It displays virus- and strain-specific epitopes and is highly immunogenic. <...> Degradation of the N-terminal domain creates a potential problem in the production of virus-specific antisera and strain-specific monoclonal antibodies and complicates the serological analysis of virus isolates. <...> Plum pox virus (PPV) is considered the most important viral pathogen of stone fruit crops. <...> Serological methods are of great importance for the diagnosis of PPV, strain identification, elaboration of PPV-resistant cultivars, epidemiological surveys and prevention of the uncontrolled spread of the virus in stone fruit plantings. <...> The CP of PPV was studied by polyacrylamide gel electrophoresis, Western blotting and immunoelectron microscopy using monoclonal antibodies 5B and 4DG5 specific to the PPV universal and strain D epitopes, respectively. <...> The purified virus particles have been shown to contain three types of subunits: full-size CP as well as the 28 and 31 kDa products of its partial proteolysis. <...> Three bands of the similar molecular weight were also detected in the analysis of fresh extracts from PPV- infected Nicotiana benthamiana tobacco leaves and a number of stone fruits (peach, plum and cherry plum), homogenized directly in the sample buffer, by Western blotting with the antibody 5B suggesting that the CP <...>