The Analysis of the Antigenic Structure of Protein Molecules (Part 2 of 3)

Glutaraldehyde is a useful tissue and molecular fixing reagents. The aldehyde moiety reacts mainly with primary amino groups to form a Schiff's base, which is reversible but reasonably stable at pH 7; a stable covalent bond may be formed by reduction with, e.g., sodium cyanoborohydride (Fig. 1). The bifunctional glutaraldehyde, (CHO-(CH2)3-CHO), successfully stabilizes protein molecules due to generally plentiful amines on their surface; bovine serum albumin has 60; 59 lysines + 1 α-amino. With some enzymes, catalytic activity after fixing is preserved; with respect to antigens, glutaraldehyde treatment can compromise their recognition by antibodies in some cases. Complicating the chemistry somewhat are the reported side reactions, where glutaraldehyde reacts with other amino acid side chains, cysteine, histidine, and tyrosine. It has also been reported that glutaraldehyde can polymerize in aqueous solution. Newer crosslinkers have been found that are more specific for the amino group, such as the N-hydroxysuccinimide esters, and are commonly preferred for forming conjugates. However, most of these linkers hydrolyze in solution, so that the activity is lost over several hours, whereas the aldehyde group is stable in solution, and may have an advantage of overall efficiency.

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Chapter 2b: The molecular antigenic structure of the TBEV

Tick-borne encephalitis - The Book ◽

10.33442/26613980_2b-3 ◽

2020 ◽

Keyword(s):

Conformational Changes ◽

Neutralizing Antibodies ◽

Lipid Membrane ◽

Cell Entry ◽

Antigenic Structure ◽

E Proteins ◽

Amino Acid Sequence Level ◽

Endosomal Membrane ◽

E Protein ◽

Golgi Network

TBEV-particles are assembled in an immature, noninfectious form in the endoplasmic reticulum by the envelopment of the viral core (containing the viral RNA) by a lipid membrane associated with two viral proteins, prM and E. Immature particles are transported through the cellular exocytic pathway and conformational changes induced by acidic pH in the trans-Golgi network allow the proteolytic cleavage of prM by furin, a cellular protease, resulting in the release of mature and infectious TBE-virions. The E protein controls cell entry by mediating attachment to as yet ill-defined receptors as well as by low-pH-triggered fusion of the viral and endosomal membrane after uptake by receptor-mediated endocytosis. Because of its key functions in cell entry, the E protein is the primary target of virus neutralizing antibodies, which inhibit these functions by different mechanisms. Although all flavivirus E proteins have a similar overall structure, divergence at the amino acid sequence level is up to 60 percent (e.g. between TBE and dengue viruses), and therefore cross-neutralization as well as (some degree of) cross-protection are limited to relatively closely related flaviviruses, such as those constituting the tick-borne encephalitis serocomplex.

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Special Protein Molecules Computational Identification

Current Proteomics ◽

10.2174/157016461704200514074413 ◽

2020 ◽

Vol 17 (4) ◽

pp. 256-257

Author(s):

Fei Guo

Keyword(s):

Protein Molecules ◽

Computational Identification

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Effect of the membrane potential on the performance of ultrafiltration membranes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19860539 ◽

1986 ◽

Vol 51 (3) ◽

pp. 539-544 ◽

Cited By ~ 3

Author(s):

Hans-Hartmut Schwarz ◽

Vlastimil Kůdela ◽

Jaromír Lukáš ◽

Jiří Vacík ◽

Volker Gröbe

Keyword(s):

Membrane Potential ◽

Concentration Polarization ◽

Ultrafiltration Membranes ◽

Membrane Cleaning ◽

Gel Layer ◽

Charged Membrane ◽

Protein Molecules ◽

Polysulfone Membranes ◽

Pressure Driven

In the pressure driven process the performance of membranes for ultrafiltration can be changed by incorporating charged groups into the membranes. sulfonation of polysulfone membranes the membrane potential is varied. On interaction of the negatively charged membrane with positively or negatively charged protein molecules the formation of a concentration polarization gel layer proceeds at different rate. Thus, the performance of the membrane can be controlled by the membrane potential. The dependence of the performance on the potential is discussed and procedures for membrane cleaning are suggested.

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