''Stelpaviricetes'' is a class of

non-enveloped A viral envelope is the outermost layer of many types of viruses. It protects the genetic material in their life cycle when traveling between host cells. Not all viruses have envelopes. Numerous human pathogenic viruses in circulation are encase ...

positive-strand RNA viruses Positive-strand RNA viruses (+ssRNA viruses) are a group of related viruses that have positive-sense, single-stranded genomes made of ribonucleic acid. The positive-sense genome can act as messenger RNA (mRNA) and can be directly translated i ...

which infect

plants Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

and

animals Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...

. Characteristic of the group is a

VPg VPg (viral protein genome-linked) is a protein that is covalently attached to the 5′ end of positive strand viral RNA and acts as a primer during RNA synthesis in a variety of virus families including Picornaviridae, Potyviridae and Calicivirid ...

protein attached to the

5'-end Directionality, in molecular biology and biochemistry, is the end-to-end chemical orientation of a single strand of nucleic acid. In a single strand of DNA or RNA, the chemical convention of naming carbon atoms in the nucleotide pentose-sugar-ri ...

of the genome and a conserved 3C- like protease from the

PA clan of proteases The PA clan ( Proteases of mixed nucleophile, superfamily A) is the largest group of proteases with common ancestry as identified by structural homology. Members have a chymotrypsin-like fold and similar proteolysis mechanisms but can have identit ...

for processing the translated

polyprotein Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. Uncatalysed, the hydrolysis of peptide bonds is extremely slow, taking hundreds of years. Proteolysis is typically catalysed by cellular enzymes called proteas ...

. The name of the group is a

syllabic abbreviation An abbreviation (from Latin ''brevis'', meaning ''short'') is a shortened form of a word or phrase, by any method. It may consist of a group of letters or words taken from the full version of the word or phrase; for example, the word ''abbrevia ...

of member orders "''stel''lavirales, ''pa''tatavirales" with the suffix ''-viricetes'' denoting a virus class.

Orders

The following orders are recognized: * ''

Patatavirales ''Potyviridae'' is a family of positive-strand RNA viruses that encompasses more than 30% of known plant viruses, many of which are of great agricultural significance. The family has 12 genera and 235 species, three of which are unassigned to ...

'' * ''

Stellavirales Astroviruses are a type of virus that was first discovered in 1975 using electron microscopes following an outbreak of diarrhea in humans. In addition to humans, astroviruses have now been isolated from numerous mammalian animal species (and are ...

References

{{Baltimore classification Viruses