His-tag and FLAG are two of the most commonly used tags in affinity purification. While both systems have positive features, disadvantages such as multiple chromatography steps, low resin binding capacity, and non-specific binding can result in lower purity and yield than desired.
Improvements on the methods and manner of delivery of ribonucleoprotein (RNP) complexes have been made in order to improve efficiency and minimize off-target effects. This blog post reviews the current state of RNP complex delivery systems.
Low protein yield is a common issue in protein purification, especially when it comes to isolating large or complex structures. In lieu of using denaturants to elute protein from an affinity column, protease elution can be a welcome alternative to give tag-free protein.
The OD 260/280 ratio is a valuable tool in protein purification; it serves as a guidepost for the purity and composition of a sample. This blog post will talk about the importance of measuring this value throughout the process of purifying proteins.
In 2013, crystallographer and UAB Professor Dmitry Vassylyev was purifying proteins for crystallography studies when he began to develop the CL7/Im7 system. At the time, no single affinity chromatography system existed that could give him the desired ultra-high purity, tag-free protein with reasonable yield in a short amount of time.
Biosimilars are functionally significant proteins with therapeutic potential. This blog post highlights the purification of several biosimilar proteins using the CL7/Im7 system.
Membrane proteins are difficult to purify due largely to their hydrophobic regions. When the proteins are in solution, these exposed regions can form strong non-specific interactions with each other, cytoplasmic proteins, or nucleic acids.
Multi-subunit proteins present roadblocks because of their size and the expression of multiple units. In this blog post, we discuss the one-step purification of ttRNAP and mtRNAP, two bacterial RNA polymerases, using the CL7/Im7 system.
This case study examines the Staley Lab’s success in using the CL7/Im7 system for their protein purification needs. Cody Hernandez, PhD candidate, shares his experience working with TriAltus’ methods to purify helicases, a mutant helicase, and several proteins.
Cas9 requires high purity in order to achieve high activity as a part of the CRISPR system for genetic modification. Due to a growing demand for Cas9 and an effort to improve its production, TriAltus conducted its own purification runs of Cas9 with success.
In the past several years, CRISPR has emerged as a powerful system for targeted gene modification. The system requires only two primary components: a guide RNA (gRNA or sgRNA) sequence and a Cas9 enzyme.
This blog post about pH in the context of protein purification is the third in a series about optimizing conditions for protein purification. Although pH is most commonly seen as an issue in ion-exchange chromatography, it also plays a critical role in affinity tag protein purification.
