The Polypeptides of Haemagglutinating Encephalomyelitis Virus and Isolated Subviral particles

Abstract

SUMMARYHaemagglutinating encephalomyelitis virus (HEV), a member of the coronavirus group, was adapted for growth in adult pig thyroid cell cultures and purified by ammonium sulphate precipitation and rate zonal centrifugation through sucrose gradients. Polyacrylamide gel electrophoresis of samples of purified virus revealed the presence of five polypeptides, four of which contained carbohydrate. The molecular weights of these proteins were I8OOOO (gp I8O), I25 ooo (gp t25), IOOOOO (gp IOO), 56o00 (p 56) and 26500 (gp 26"5). After treatment of the virus with the non-ionic detergent Nonidet P4o, two subviral components were isolated. As RNA-containing particle, sedimenting in sucrose gradients at the same rate as untreated virus, was analysed and found to contain two polypeptides, p 56 and gp 26"5. The second complex sedimented at a much slower rate and contained three glycoproteins gp I8O, gp t25 and gp too. Comparison of these findings with data published for other members of the coronavirus group is discussed.

In vivo and in vitro Models of Demyelinating Diseases

“…the diameter of the helical nucleocapsid of the paramyxoviruses, measuring 15-19 nm [24,32,33], is about double the width of the coronavirus cores. According to another recent interpretation, the coronavirus nucleocapsid structure is described as a circular, dense, inner component, about 60 nm in diameter [7], Our new evidence, coupled with information ob tained on disrupted negatively stained 229E virions [29,31] and on another representative of the group [30], indicate that the architecture of the coronaviruses simulates that of the orthomyxo-and paramyxoviruses, although the coronaviruses, unlike the other two groups, possess a single-stranded RNA genome of the + sense. From this observation it may be con cluded that polarity of the RNA genome and helical conformation of the nucleoprotein are not necessarily interrelated.…”

Structural Proteins and Glycoproteins of Infectious Bronchitis Virus Particles Labeled during Growth in Chick Embryo Cells

“…An additional glycoprotein, GP125, has also been reported (table I). The glycoproteins larger than the presumptive nucleoprotein are re moved from virions either by limited proteoly tic digestion or by nonionic detergent (1% Nonidet P-40), and thus they comprise the envelope proteins; the smallest glycoprotein appears to be largely located internal to the envelope because it is often resistant to such treatments [3][4][5]. Sturman and colleagues [6] showed further that the smallest glycoprotein, GP23,ofmurine coronavirus A59 interactswith viral RNA in the nucleocapsid, and that the larger (external or peplomeric) envelope pro tein is GP90 and its apparent dimer G P 180.…”

Structural Polypeptides of Coronavirus IBV

“…The polypeptide composition of several mammalian coronaviruses has been determined, namely human coronavirus (HCV) strains 229E (Hierholzer, 1976: Macnaughton, 1980) and OC43 (Hierholzer et al, 1972), transmissible gastroenteritis virus (TGEV) of pigs (Garwes & Pocock, 1975;Garwes et al, 1976), haemagglutinating encephalomyelitis virus (HEV) of pigs (Pocock & Garwes, 1977), mouse hepatitis virus (MHV) strains A59 (Sturman, 1977;Bond et al, 1979), JHM (Wege et al, 1979: Bond et al, 1979 and MHV3 (Macnaughton, 1980). In general, the polypeptides of these coronaviruses can be assigned to four size-classes (Sturman, 1977).…”

“…ranges of 130 × 103 to 200 x 10 3 and 89 x 103 to 125 x 103 characterize polypeptides in size-classes one and two respectively. Polypeptides of both these classes are glycosylated and constitute the virion spikes (S) (Bingham, 1975;Garwes & Pocock, 1975;Pocock & Garwes, 1977;Sturman, 1977;Wege et al, 1979;Macnaughton, 1980;Collins & Alexander, 1980b). Non-glycosylated polypeptides of 50 x 103 to 60 x 103 tool.…”