Identification of mumps virus protein and lipid composition by mass spectrometry

Abstract

BackgroundMumps virus is a negative-sense, single stranded RNA virus consisting of a ribonucleocapsid core enveloped by a lipid membrane derived from host cell, which causes mumps disease preventable by vaccination. Since virus lipid envelope and glycosylation pattern are not encoded by the virus but dependent on the host cell at least to some extent, the aim of this work was to analyse L-Zagreb (L-Zg) mumps virus lipids and proteins derived from two cell types; Vero and chicken embryo fibroblasts (CEF). Jeryl Lynn 5 (JL5) mumps strain lipids were also analysed.MethodsVirus lipids were isolated by organic phase extraction and subjected to 2D-high performance thin layer chromatography followed by lipid extraction and identification by matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Virus samples were also subjected to gel electrophoresis under denaturating conditions and protein bands were excised, in-gel trypsinized and identified by MS as well as tandem MS.ResultsResults showed that lipids of both mumps virus strains derived from Vero cells contained complex glycolipids with up to five monosaccharide units whereas the lipid pattern of mumps virus derived from CEF was less complex. Mumps virus was found to contain expected structural proteins with exception of fusion (F) protein which was not detected but on the other hand, V protein was detected. Most interesting finding related to the mumps proteins is the detection of several forms of nucleoprotein (NP), some of which appear to be C-terminally truncated.ConclusionsDifferences found in lipid and protein content of mumps virus demonstrated the importance of detailed biochemical characterization of mumps virus and the methodology described here could provide a means for a more comprehensive quality control in vaccine production.Electronic supplementary materialThe online version of this article (doi:10.1186/s12985-016-0463-0) contains supplementary material, which is available to authorized users.

Mass spectrometry-based investigation of measles and mumps virus proteome

“…Occurrence of protein N in multiple bands at MM equal and lower than MM aa is in agreement with previous results which hypothesized that minor bands ranging from 40 to 55 kDa belong to breakdown products of N protein or its truncated forms [ 23 , 32 ]. It is also interesting to notice that the intensity of the 55–56 kDa band in the samples is typically higher than of that at 59 kDa.…”

“…The genomes of MEV and MUV are well explored, but the proteome of MUV was only recently investigated by mass spectrometry (MS) [ 32 ], which is currently the dominant method in the field [ 49 ]. This is the first investigation of MEV proteome by MS, to the best of author’s knowledge.…”

“…These early investigations relied on gel electrophoresis for determination of molecular masses of proteins, combined with labelling newly synthesized proteins by radioactive amino acids ( 14 C-labeled amino acid mixtures, 3 H-leucine or 35 S-methionine), and detection of glycoproteins by incorporation of 3 H-glucosamine. Recently, MUV proteome was investigated by mass spectrometry for the first time and the presence of 6 virus polypeptides was confirmed: L, HN, NP, P, M and V [ 32 ].…”

“…Presence of HCPs in virus preparations is important both for basic research of the biology of these viruses, as well as for the vaccine production in industry because it means that the vaccine is not only carrying viral, but also HCP antigens [ 34 ]. Early investigations of MEV and MUV already reported the presence of cellular actin in virions [ 21 , 26 , 28 ], and additional HCPs such as fibronectin, clathrin and histones were detected in MUV samples investigated recently [ 32 ]. There are indications that some HCPs are specifically taken up by the viral particles, by direct interactions with viral proteins [ 34 – 36 ], but HCPs might also be incorporated non-specifically [ 37 ], can be adsorbed to the outer surface of the virion, or be present as contamination arising from the presence of cellular debris or extracellular vesicles (ECVs) in virus preparations [ 38 , 39 ].…”

Recombinant mumps virus as a cancer therapeutic agent

“…The rate of infectivity differs between the cell lines which is likely due to influence of one or more factors; interferon pathway-related genes, various cellular factors (cell cycle modulators, apoptotic machinery, NF-κB, and APOBEC3) or receptors and coreceptors expression levels. 14–18 More detailed study is warranted to understand the interaction between virus and host cell. Another interesting phenomenon of mumps virus infection is cytopathic effect (CPE).…”