MICROBExpress™ Bacterial mRNA Enrichment Kit (Invitrogen™)

The MICROBExpress™ Bacterial mRNA Enrichment Kit is for the purification of bacterial mRNA by removing rRNA from total RNA. Sufficient reagents for 20 mRNA purifications, each from 10 μg of total RNA are provided. Features of the MICROBExpress™ Kit:

• Dramatically increase the sensitivity of array analyses and other procedures
• Removes >95% of 16S and 23S rRNA from bacterial RNA
• Simple procedure takes less than 2 hours
• Works with many Gram positive and Gram negative bacteria

Rapid purification of bacterial mRNA
Isolating mRNA from bacteria has been virtually impossible, until now. The MICROBExpress™ Kit uses a novel technology to remove >95% of the 16S and 23S rRNA from total RNA of E. coli and other bacterial species. The kit is suitable for mRNA purification from a broad spectrum of Gram positive and Gram negative bacteria. The mRNA isolated with the MICROBExpress™ Kit is a superior template for synthesizing labeled cDNA for array analysis, and is ideal for quantitative RT-PCR, northern applications, and cDNA library construction. Efficient removal of 16S and 23S rRNA from bacterial RNA dramatically increases sensitivity in downstream procedures (see figure).

Start with any total RNA sample
This host-bacterial cell total RNA mixture can be obtained by a variety of RNA isolation methods. The MICROBExpress™ Kit specifically removes rRNAs; small RNAs (i.e., tRNA and 5S rRNA) are not removed. Using total RNA that lacks small RNAs as the starting material for MICROBExpress™ Kit produces the highest possible level of mRNA enrichment (see accessory products). In the first step of the MICROBExpress™ Kit procedure, total RNA is mixed with an optimized set of capture oligonucleotides that bind to the bacterial 16S and 23S rRNAs. Next, the rRNA hybrids are removed from the solution using derivatized magnetic microbeads. The mRNA remains in the supernatant and is recovered by ethanol precipitation.

Accessory products
A magnetic stand is required for use this kit. They are available in several formats, including the Single Place Magnetic Stand (Cat. No. AM10026), 6 Tube Magnetic Stand (Cat. No. AM10055), and 96-well Magnetic Stands (Cat. Nos. AM10027 and AM10050). The RiboPure™-Bacteria Kit (Cat. No. AM1925) is ideal for the purification of total RNA lacking small RNAs. Small RNAs can be removed from total RNA using the MEGAclear™ Kit (Cat. No. AM1908).