Streptavidin - Pharmavidin.com

Streptavidin | Bacterial Streptavidin | Iodinated Streptavidin

Due to its RYD segment, streptavidin generates number of false positive results where Neutralite avidin doesn’t. This absence of RYD segment in Neutralite avidin improves drastically the quality of the IVD’s.

Streptavidin | Bacterial Streptavidin | Iodinated Streptavidin

 Streptavidin is a 60 kDa protein purified from the bacterium Streptomyces avidinii. Streptavidin homo-tetramers have an extraordinarily high affinity for biotin (also known as vitamin B7). With a dissociation constant (Kd) on the order of ≈10−14 mol/L,[1] the binding of biotin to streptavidin is one of the strongest non-covalent interactions known in nature (wikipedia.org).

Homologous residues/domains in both proteins are shown in bold type. Positively charged residues (Lys, Arg) are underlined. The RYD-containing sequence in streptavidin, which is homologous to that of fibronectin, appears in bold red. The N- and C-terminal sequences clipped by post-secretory processing (via proteolytic cleavage) on streptavidin are shown in purple. The position of the sugar residue, linked to Asn-17 of avidin in the typical NXT(S) type carbohydrate-containing consensus sequence, is identified by a star (*). Tyr-33 & -43, the nitrated amino acid residue in Nitro-Avidin & -Streptavidin, respectively, is similarly (*) identified. Cys-4 & 83 formed a disulfide bridge in native avidin; natural variant (Ile-34→Thr-34) in ~50% of the molecules.

Streptavidin | Bacterial Streptavidin | Iodinated Streptavidin

 Streptavidin is a chemically & enzymatically modified avidin characterized by a neutral isoelectric point and the absence of surface glycans. NeutraLite Avidin is carbohydrate-free and neutral, with the double advantage of the presence of a large number of amino acids available for derivatization, and the absence of RYD sequences. Altogether, these molecular characteristics yield the lowest nonspecific binding among known biotin-binding proteins, yet a specific activity near the theoretical maximum of approximately 14 μg/mg of protein Streptavidin | Bacterial Streptavidin | Iodinated Streptavidin

Neutralite - Pharmavidin.com

 

Neutralite| Neutralite Avidin | Neutralite Protein | Nitroavidin Derivatives | Neutralite Equivalent

Neutralite Avidin is a chemically & enzymatically modified avidin characterized by a neutral isoelectric point and the absence of surface glycans. Without RYD segment, Neutralite avidin increases drastically the quality of the IVD’s.

Neutralite| Neutralite Avidin | Neutralite Protein | Nitroavidin Derivatives | Neutralite Equivalent

Neutralite| Neutralite Avidin | Neutralite Protein | Nitroavidin Derivatives | Neutralite Equivalent

Native – glycosylated & basic – avidin is treated with an endoglycosidase F (Endo-F1) to release the glycans located on each monomer asparagine 17 (Asn-17), leaving a surfacial GlcNAc-Asn residue (see caption under). A chemical mutation transforms a precise number of surfacial arginine (Arg) to nor-lysine (Nor-Lys) residues, and the isoelectric point (pI) is standardized to a neutral – slightly acidic - value. The end product is a highly standardized deglycosylated acetylated avidin, ie Neutralite avidin, characterized by an excellent solubility, absence of non-specific binding properties (lectin affinity, electrostatical interaction, RYD aminoacid sequence) and similar-to-native-avidin number of free surfacial primary amino group for derivatization.

Neutralite| Neutralite Avidin | Neutralite Protein | Nitroavidin Derivatives | Neutralite Equivalent

NeutraLite Avidin is carbohydrate-free and neutral, with the double advantage of the presence of a large number of amino acids available for derivatization, and the absence of RYD sequences. Altogether, these molecular characteristics yield the lowest nonspecific binding among known biotin-binding proteins, yet a specific activity near the theoretical maximum of approximately 14 μg/mg of protein.

Neutralite| Neutralite Avidin | Neutralite Protein | Nitroavidin Derivatives | Neutralite Equivalent

Nitrolite - Pharmavidin.com

Nitrolite | Nitrolite Avidin

Nitrolite encompasses the advantage of reversibility of biotin-binding and the absence of non-specific binding which may represent a real plus in affinity chromatography.

The selective nitration of tyrosine residues in three of the four biotin-binding sites of Neutralite avidin considerably reduces the affinity of the protein for biotinylated molecules above pH 9. Consequently, biotinylated probes can be adsorbed at neutral pH and released at pH ~10. Free biotin blocks the remaining high-affinity biotin-binding sites that have not been nitrated. Nitroavidin is particularly useful for separating and purifying biotin conjugates from complex mixtures. Nitroavidin also provides a regenerable capture reagent for functionalization of surface plasmon resonance (SPR) immunosensors2. In its neutral/deglycosylated form (NitroLite Avidin), it encompasses the advantage of reversibility of biotin-binding and the absence of nonspecific binding which may represent a real plus in affinity chromatography. The biotin-binding capacity of Nitroavidin derivatives is typically min 10 µg free biotin per mg protein.

Nitrolite | Nitrolite Avidin

Nitrolite Avidin  is a chemically & enzymatically modified avidin characterized by a neutral isoelectric point and the absence of surface glycans. NeutraLite Avidin is carbohydrate-free and neutral, with the double advantage of the presence of a large number of amino acids available for derivatization, and the absence of RYD sequences. Altogether, these molecular characteristics yield the lowest nonspecific binding among known biotin-binding proteins, yet a specific activity near the theoretical maximum of approximately 14 μg/mg of protein

Avidin - Pharmavidin.com

Avidin | Avidin biotin | Native Avidin | Nitrolite Avidin

All of our standard and customized products are produced from avidin with the same standard. Pharmavidin is able to actively participate in research programs that aim to develop a new avidin derivative for new applications.

Avidin | Avidin biotin | Native Avidin | Nitrolite Avidin

Avidin is a 66-KDa glycoprotein synthesized in the oviduct of a hen and deposited in the albumen of its eggs. It binds the water-soluble vitamin biotin (vitamin B7 or H) very tightly – irreversibly – and specifically, with an outstanding dissociation constant of ~10-15 M. The protein, its stability and affinity for biotin, have been extensively investigated and characterized. It folds into a quaternary tetramer structure made of 4 subunits of identical amino acid composition and sequence, each containing 9 lysine residues.

Avidin is highly cationic with an isoelectric point (pI) of about 10.5. Glycosylation occurs at the Asn-17 residue, in a typical NXT(S) or Asn-Xxx-Thr(Ser) type carbohydrate-containing consensus sequence. Oligosaccharide components (heterogeneous structures composed largely of mannose (Man) and N-acetylglucosamine (GlcNac)) and positively charged amino acid residues (Lys & Arg) can interact nonspecifically with lectins and negatively charged cell surfaces and nucleic acids, thereby potentially causing nonspecific bindings in diagnostic and therapeutic applications1. Bioengineering methods have been developed to suppress such nonspecific bindings. The result: NeutraLite Avidin, a nonspecific binding-free form of native avidin, in which the signal/background ratio can be customarily adjusted (see NeutraLite Oligomers) and the biotin-specific binding can be made reversible (see Nitroavidin, Avidin Monomer, Iminobiotin) to accommodate an ever larger range of applications.  

Avidin | Avidin biotin | Native Avidin | Nitrolite Avidin

Sugar heterogeneity of avidin. Comparison of glycopeptides from ovalbumin and avidin shows that the avidin carbohydrate contains at least three distinct oligosaccharide structural types of similar size as shown above; N-linked glycan at Asn-17 consists of GlcNAc(beta1-2)Man(alpha1-3)[GlcNAc(beta1-4)][Man(alpha1-?)Man(alpha1-6)]Man(beta1-4)GlcNAc(beta1-4)GlcNAc. Some terminal galactose may even be present on some glycans. Avidin | Avidin biotin | Native Avidin | Nitrolite Avidin

Company - Pharmavidin.com

Company

Pharmavidin meets the growing demand from industries operating in the biotechnology and pharmaceuticals fields that are looking for innovative high-performance avidin-based products certified to the highest quality standards.

Avidin | Neutralite | Streptavidin | Biotin

Avidin | Neutralite | Streptavidin | Biotin

 

 

 

Pharmavidin is currently the worldwide leader in one out of three different product lines based on Belovo Eggs Technology. With the ambition of becoming the worldwide leader in all products for parenteral applications, Pharmavidin has heavily invested in R&D, equipment and infrastructure, as well as industry standard certifications. We are confident that the quality we are able to offer our clients will be the foundation of our success.Avidin | Neutralite | Streptavidin | Biotin

Pharmavidin not only offers cutting-edge products in each of their categories, but also expert advice from its team of researchers, in order to fully optimize the products' innovative potential, with the objective of guaranteeing performance and reliability.
We are planning to offer two new avidin derivatives over the next five years, which will cater to the current demand for products with innovative features.

Avidin | Neutralite | Streptavidin | Biotin