EiCsm6

Alternate Names:

Enteroccocus italicus Csm6, CRISPR type III-A associated protein Csm6

UniProt Number:

E6LHV2

Overview:

EiCsm6 is an ancillary ribonuclease associated with the type III CRISPR-Cas system of Enterococcus italicus. Like other Csm6 family proteins, EiCsm6 consists of a CARF (CRISPR-associated Rossman fold) domain, which binds cyclic oligoadenylate (cOA), and a HEPN (Higher Eukaryotes and Prokaryotes Nucleotide binding) domain, which possesses ribonuclease activity (1). The RNA degradation activity of EiCsm6 is stimulated by cOA and functions to protect the bacterial cell from invasive genetic elements like bacteriophages and plasmids (2, 3).

Accession Number:

WP_007208953.1

Formulation:

Protein stored in 50 mM sodium phosphate, pH 7.5, 300 mM NaCl, 200 mM imidazole, 1 mM DTT, 10% glycerol

References:

1. Niewoehner O, Jinek M. 2016. Structural basis for the endoribonuclease activity of the type III-A CRISPR-associated protein Csm6. RNA. 22(3):318-29.
2. Rostøl, J.T., Marraffini, L.A. 2019. Non-specific degradation of transcripts promotes plasmid clearance during type III-A CRISPR–Cas immunity. Nat Microbiol 4:656–662.
3. Niewoehner O, Garcia-Doval C, Rostøl JT, Berk C, Schwede F, Bigler L, Hall J, Marraffini LA, Jinek M. 2017. Type III CRISPR-Cas systems produce cyclic oligoadenylate second messengers. Nature. 548(7669):543-548.

Storage and Stability:

Store at –70°C. To avoid repeated handling and multiple freeze/thaw cycles, aliquot product into smaller quantities.

Concentration:

0.5 μg/μl
19.38 pmol/μg

Purity:

>95%

Molecular weight:

Calculated: 51.9 kDa
Observed: ~50 kDa

Recommendation:

Always include RNase inhibitor at recommended concentrations in Cas enzyme reactions.