Principles and reactions of protein extraction, purification, and characterization: Ahmed, Hafiz

Abstract

Ahmed, Hafiz, CRC Press, Boca Raton, FL, 2005, 432 pp., ISBN 0-8493-2034-8, $128.95. The author's purpose for writing this book is stated clearly in the preface: “The book presents techniques (both classical and recent) for protein extraction, purification, and characterization, and discusses their underlying principles and working procedures including comments on their advantages and disadvantages.” The book, with protocols and procedures (and spiral-bound), is intended for use in the research laboratory. The advent of proteomics has stimulated the publication of many books on the general topics of protein extraction and characterization. What are the distinctive characteristics of this volume, and how will it fare in the marketplace? The book is comprised of seven chapters: 1) Extraction of Protein; 2) Estimation of Protein; 3) Electrophoretic Analysis of Protein; 4) Purification of Protein; 5) Antibodies: Structures, Interactions, and Production; 6) Antibody Labeling, Antibody Detection, and Immunochemical Techniques; and 7) Purification of Glycoproteins and Analysis of Their Oligosaccharides. The sizes of most chapters (average number of pages = 45) are directly related to the importance of the topics; however, Chapter 6 has twice the average, which makes for a long and cumbersome read. Each chapter is organized in a logical fashion beginning with an introduction, moving on with discussions of procedures, and ending with references. Most of the text reads well as it is broken into bite-size pieces with a generous use of numbered headings and subheadings. The most positive features in each chapter are the occasional placement of actual laboratory procedures (called “working procedures”) and discussions on the advantages and disadvantages of each technique/method, often presented in tabular format. This comparison of methods and advice on when certain methods should be used is perhaps the most valuable feature of the book. All methods are described in complete detail beginning with chemical principles and reactions, and continuing with limitations of the procedure. Examples of this thorough coverage are seen throughout the book. In the chapter on protein estimation (Ch. 2), the methods discussed include A280, A205, Biuret, Lowry, BCA, Bradford, Colloidal Gold, Ninhydrin, Fluorescamine, o-Phthalaldehyde, CBQCA, and NanoOrange. Chapter 2 also includes a useful table comparing commercial protein assay kits. Chapter 3 has extensive descriptions of all electrophoretic techniques; however, with only a brief mention of two-dimensional and modern capillary electrophoresis. The expansive and all-inclusive coverage of methods seems to be a hallmark of the book as each chapter has an encyclopedic listing of procedures. Unfortunately, many of the techniques covered are those of the past and are rarely used today. Most of the methods are based on chemical analysis rather than application of modern instrumental techniques. This is especially noticeable in the chapter on glycoprotein analysis (Ch. 7) which has an exhaustive listing of colorimetric methods for saccharide analysis, but no mention of nuclear magnetic resonance or mass spectrometry techniques. The lack of current methods is also noted in the references for each chapter. Only two chapters (Chs. 1 and 2) have references from the 21st century (2001), and the majority of references are in the 1980s and 1990s. Although the book is meant for researchers in the rapidly expanding field of proteomics, those working in the field rely on modern techniques. It is also discouraging to note the “missed opportunities” where the author could have greatly enhanced the book by including currently used techniques. Some of the most glaring examples, which are lacking, include the incorporation of computers and websites into the analysis of proteins; discussion of roto-stator homogenizers; and the preparation, extraction, and purification of recombinant proteins. Only about three pages are devoted to recombinant proteins, and this describes extraction of proteins from inclusion bodies. There is no mention of the use of fusion proteins or His-tagged columns for recombinant protein separation. Although book errors and typos are few, some are of serious enough nature to be reported: on page 1 a double-headed arrow, usually representing “resonance,” is used for an equilibrium reaction; in the protein estimation chapter, it is stated that amino acids that have absorbance at 280 nm include tryptophan, tyrosine, phenylamine (should be phenylalanine), and histidine (neither Phe nor His has strong absorption at 280 nm); there is reference in Chapter 7 to “Howarth” carbohydrate structures; and an oxygen atom is substituted for a carbon atom in Fig. 6.15. This book may have a limited value to researchers who work daily with proteins. It certainly provides an historical perspective to protein extraction and analysis. It is also of interest to those working with membrane proteins and glycoproteins.