Table Gallery

Table 1 Virus-associated proteins of coronaviruses


Protein		Coronavirus^a

Spike glycoprotein	S	180-220
Membrane protein	M	23-35
Nucleocapsid protein	N	50-60
Small-envelope protein	E	9-12
Hemagglutinin-esterase protein	HE	65

^a, apparent Mr estimated by electrophoresis ( 10³)

Table 2 Virus-associated proteins of toroviruses


Protein		Torovirus^a

Spike glycoprotein	S	200
Membrane protein	M	27
Nucleocapsid protein	N	19
Small-envelope protein	E	nk
Hemagglutinin-esterase protein	HE	65

^a, apparent Mr estimated by electrophoresis ( 10³). nk, presence not known.

Table 3 Features of coronaviruses and toroviruses


Feature	Coronavirus	Torovirus

Enveloped	+	+
Linear positive-sense ssRNA with poly(A) tail	+	+
5polymerase gene-structural protein genes 3	+	+
3 co-terminal nested set of 4 subgenomic mRNAs	+	+
Only 5 unique region of mRNAs is translationally active	+	+
Ribosomal frameshifting in the polymerase gene	+	+
M protein with three membrane-spanning sequences	+	+
Intracellular budding	+	+
Genome size (kb)	27-31	~25
5 leader sequence	+	-
Core shell	+	-
Nucleocapsid	helical	tubular
Prominent spikes	+	+
Coiled-coil structure in spikes	+	+