抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Summary: Jalview Version 2 is a system for interactive WYSIWYG editing, analysis and annotation of multiple sequence alignments. Core features include keyboard and mouse-based editing, multiple views and alignment overviews, and linked structure display with Jmol. Jalview 2 is available in two forms: a lightweight Java applet for use in web applications, and a powerful desktop application that employs web services for sequence alignment, secondary structure prediction and the retrieval of alignments, sequences, annotation and structures from public databases and any DAS 1.53 compliant sequence or annotation server.

Availability: The Jalview 2 Desktop application and JalviewLite applet are made freely available under the GPL, and can be downloaded from www.jalview.org

Contact: g.j.barton@dundee.ac.uk

/pdf/jalview-version-2-a-multiple-sequence-alignment-editor-and-3pguchayjh.pdf

Jalview Version 2--a multiple sequence alignment editor and analysis workbench.

Encoding and decoding hydrogen-bond patterns of organic compounds

Infrared spectroscopy of proteins.

http://theory.bio.uu.nl/immbio/Marks91.pdf

By-passing immunization: Human antibodies from V-gene libraries displayed on phage

Where are we in our understanding of enzyme catalysis? The gloomier view is that protein structure and enzyme function are the finely balanced end-products of many weak interactions that can be summed only by massive computing power, and more precise parameterization than we enjoy at present. The cheerier position is that proteins are built on definable principles, and that enzymes use recognizable catalytic devices that will allow us to understand how existing enzymes work and to design new ones. To assess which interpretation is the more realistic, the simple reaction catalysed by triosephosphate isomerase is considered here. This examination illustrates some of the catalytic features of enzymes that are understood, and exposes a few that are not. But overall, the question turns out to have an optimistic answer.

Enzyme catalysis: not different, just better.

Publisher Summary This chapter discusses the photoaffinity labeling which could be used as a method that allows to unleash the reagent at a particular time and place, when the chemical affinity labeling restricts it. The chapter notes that the possibility that a labile group of appropriate reactivity cannot be incorporated into the ligand molecule without excessive disturbance of the recognition process, there are two limitations to the affinity labeling approach. The first challenge; the range of chemical reactivity of groups that can be incorporated into the ligand is limited by the fact that these groups must not react so rapidly with water that they are destroyed hydrolytically before the ligand that carries them can reach the binding site. And secondly, it is becoming clear that some biological problems require a reagent whose reactivity remains masked until the experimenter chooses to activate it. Both of the two limitations of classical chemical affinity labeling discussed above can in principle be circumvented by the use of a photogenerated reagent.

[8] Photoaffinity labeling

TRANSFORMATIONS THAT REQUIRE BIOTIN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 195 Structural Similarities . . .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . 196 Functional Similarities . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . 198 THE CARBOXYLATION OF BIOTIN . . . . . . . . . , 199 B icarbonate or Carbon Dioxide as Substrate? . . . . . . . . . . . . . . . ... ..... . . .. . . . . . . . . . . . . . . . . . . . 200 Nor O .. Carboxybiotin as Product? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .. . . . . . . . . . . . . . . . . 200 Some Suggested Mechanisms and Efforts to Discriminate Amongst Them . . . . . . . . . . . . 200 The Mechanism of Biotin Carboxylation 206 THE CARBOXYLATION OF CARBON ACCEPTORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 Is the Carboxyl Transfer Stepwise or Concerted? . . . . . . . . . . . . . . . . . . . . . . .. .... . . . . . . . . . . . . . . 212 Tritium Transfer in Transcarboxylase . . .. .. . . . . . . . . . . . . . . . . . . . . . . . . .. ... . . . . . . . . . . . . . . . . . . . . . 215 THE MECHANISTIC PATHWAY FOR CARBOXYLASES _ _ _ _ _ _ _ _ _ _ _ _ _ . . . . . . . . . . . . . . . . . . 216 WHY BIOTIN?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..... . . . . . . . . .. ....... 216

The Mechanism of Biotin-Dependent Enzymes

Perfection in enzyme catalysis: the energetics of triosephosphate isomerase

It is now possible, by site-directed mutagenesis of the gene, to change any amino acid residue in a protein to any other. In enzymology, application of this technique is leading to exciting new insights both into the mechanism of catalysis by particular enzymes, and into the basis of catalysis itself. The precise and often delicate changes that are being made in and near the active sites of enzymes are illuminating the interdependent roles of catalytic groups, and are allowing the first steps to be taken toward the rational alteration of enzyme specificity and reactivity.

https://science.sciencemag.org/content/sci/236/4806/1252.full.pdf

Jeremy R. Knowles

Papers

Enzyme catalysis: not different, just better.

[8] Photoaffinity labeling

The Mechanism of Biotin-Dependent Enzymes

Perfection in enzyme catalysis: the energetics of triosephosphate isomerase

Tinkering with enzymes: what are we learning?