RNA polymerase principal sigma factor hrdB
The shelf life is related to many factors, storage state, buffer ingredients, storage temperature and the stability of the protein itself. Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. The shelf life of lyophilized form is 12 months at -20°C/-80°C.
Repeated freezing and thawing is not recommended. Store working aliquots at 4°C for up to one week.
Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. This sigma factor is the primary sigma factor during exponential growth. Its activity is stimulated by RbpA.