ChromoBlog

Immunoprecipitation (IP) is a technique used to isolate a protein from a cellular extract. The protein of interest (POI) is recognized by a specific antibody (Ab) conjugated to beads. Different antibody formats can be used in IP, e.g., a full-length Ab, a Fab-fragment, or a Nanobody. Below, we discuss the advantages and limitations of the different Ab formats.

ChromoTek and Proteintech recently launched Nanobodies against the SARS-CoV-2 virus. These Nanobody clones were originally developed by the group of Ulrich Rothbauer at the Natural and Medical Sciences Institute, Reutlingen, Germany. In our guest blog, Teresa Wagner and Ulrich Rothbauer discuss the development of these Nanobodies and why Nanobodies are versatile alternatives to classical antibodies in SARS-CoV-2 research.

Nanobody-Fc fusion - An alternative Nanobody format that combines its special epitope binding properties with the detection options for Fc-domains

What are heavy chain antibodies?

SNAP-tag and CLIP-tag are self-labeling protein tags. The SNAP-tag protein and the CLIP-tag protein can be fused to a protein of interest (POI) and used for cellular and biochemical analysis.

HaloTag is a protein tag. The HaloTag protein can be fused to your protein of interest (POI) which enables it for cellular and biochemical analysis. It can also be used for live cell imaging.

New iST Nano-Trap kits for immunoprecipitation (IP) and sample preparation for mass spectrometry (MS) in just 4 easy steps:

Bispecific T cell engagers are bispecific antibodies designed to link T cells with cancer cells. The simultaneous binding of the bispecific antibody to T cell and tumor cell initiates the activation of the T cell. For this purpose, the bispecific antibody carries two antigen binding domains against the T cell (often CD3 T cell receptor) and against a cell surface protein of the tumor cell.

ChromoTek offers two bispecific T cell engagers:

Nanobodies are the binding domains of heavy chain only antibodies from Camelids. Nanobodies can be recombinantly produced in bacterial and other animal-free expression systems depending on the actual Nanobody construct. In contrast, classical IgG antibodies are composed of two heavy chains and two light chains and are traditionally produced using hybridoma technlogies or are isolated from a host’s blood.

Introduction

Fluorescent proteins (FPs) have been used as protein tags since the mid-1990s mainly for cell biology and fluorescence microscopy. These tags have not only revolutionized cell biology by enabling the imaging of almost any protein, they are also used in biochemical applications. An important example is the immunoprecipitation and affinity purification of FP-tagged proteins, which was enabled by the development of affinity resins with high yield, purity, and affinity such as ChromoTek’s Nano-Traps (https://www.chromotek.com/products/detail/product-detail/nano-traps/).

In this blog we provide a review of

• green fluorescent proteins
• red fluorescent proteins
• self-labelling proteins, that require the covalent coupling of a fluorescent molecule