ANALYTICAL BIOCHEMISTRY 204,412-413 (1992)

BOOK REVIEWS

Electrophoresis of Large DNA Molecules: Theory and Appli-

cations. Edited by ERIC LAI AND BRUCE W. BIRREN. Cold Spring Harbor Laboratory Press, Plainview, New York, 1999.156 pp. $34.00

This volume is the first in a series called “Current Communications in Cell and Molecular Biology,” edited by John Inglis and Jan A. Witkowski of the Cold Spring Harbor Laboratory. The book grew out of a Banbury Conference in March 1990, where theoreticians, biophys- icists, and molecular biologists gathered to discuss the use of pulsed field gel electrophoresis (PFGE) in separating large DNA molecules. The emerging consensus on the mechanism of PFGE is reflected in the invited chapters compiled here.

The first two chapters in the book provide the background for un-

derstanding DNA gel electrophoresis. The chapter by Lerman and Sinha is a reminder that the overriding concern in any electrophoretic separation is resolution, i.e., the difference between band width and band separation. A workable, but somewhat complicated, definition of gel resolution length is proposed and illustrated. The chapter by Kirkpatrick describes the physical and chemical properties of differ- ent types of agarose and discusses the effect of electroendosmosis on the observed electrophoretic mobilities. Current controversies about agarose gel structure are also discussed briefly.

The next two chapters describe the velocity and conformational dynamics of DNA during PFGE, as studied by the technique of linear

dichroism. The chapter by Akerman, Jonsson, Moore, and Schellman starts with a short description of the linear dichroism experiment, which is probably unfamiliar to many readers. The electrophoretic orientation and disorientation of DNA in pulsed electric fields are then described in detail. The reorientation times are useful because

they can be used to estimate PFGE pulse times. In the next chapter, Holzwarth, Whitcomb, Platt, Crater, and McKee describe the use of fluorescence-detected linear dichroism to determine the velocity of DNA molecules during PFGE. The results are compared with the predictions of various theoretical models.

The chapter by Smith, Gurrieri, and Bustamante describes the fluo- rescence microscopy of individual DNA molecules undergoing gel elec- trophoresis in conventional and pulsed electric fields. Kinked and

U-shaped conformations are frequently observed, presumably due to trapping of the DNA molecules by the gel matrix. Computer simula- tions suggest that both reptation and hook/kink formation are neces- sary to obtain size-dependent separations. The theory of gel electro-

Guide to Electroporation and Electrofusion. Edited by DONALD

C. CHANG, BRUCE M. CHASSY, JAMES A. SAUNDERS, AND ARTHUR E. SOWERS. Academic Press, San Diego, 1991. 581 pp. $45.00.

The preface to this book states that it is written to satisfy the needs of a broad range of scientists, of differing levels of expertise, and in a broad and ever-growing range of applications associated with electro- fusion and electroporation. To accomplish this ambitious goal, the editors have gathered together chapters from a wide variety of au- thors and assembled them into four main areas.

Part II of the book will be of most immediate use to the beginner. It presents a series of chapters with a broad spectrum of applications of

phoresis is discussed in more detail by Deutsch in the next chapter. Various reptation models are compared, and the effects of kink mo- tion, chain pinning, and knot formation are described. Numerical sim- ulations show that DNA cycles between extended and compact con- formations during PFGE, as observed by electron microscopy. This chapter is particularly useful for the nonspecialist, who has neither the background nor the inclination to read the more mathematical treatments of reptation theory.

Turmel, Brassard, Forsyth, Hood, Slater, and Noolandi present an extensive discussion of a new type of pulsing regimen called zero-inte- grated field electrophoresis (ZIFE). ZIFE is basically a version of field inversion electrophoresis (FIGE), in which the product of pulse time

and voltage is kept nearly equal in the forward and reverse directions. The ZIFE protocol minimizes the band inversions commonly ob- served in FIGE. An automated electrophoresis workstation designed to implement ZIGE is also described briefly.

The final chapter, by Van Ommen, Den Dunnen, Lehrach, and Poustka, gives a brief overview of the use of PFGE in genetic map- ping, chromosomal rearrangements and diagnostic applications. Some of the problems inherent in physical mapping are described briefly, but this chapter is too short and too broadly based to more than hint at the various topics covered. More detail, or more refer- ences to the original literature, would have been useful.

Overall, this small volume provides an integrated view of the experi- mental and theoretical basis of PFGE. All biophysical methods and theories are described in nontechnical language, so that the book is accessible to readers from a variety of disciplines. Unlike most com- pendia, the results in different chapters are correlated with each other, making it easy to see that the various techniques give comple- mentary information. This interrelationship is also a weakness; the reader may be left with the erroneous impression that the mechanism of PFGE is completely understood. Few of the authors describe current controversies in their fields; on-going problems and unsolved questions are mentioned by the Editors in a short Perspective at the end of the volume. Nevertheless, this book provides a sound introduc- tion to the theory of PFGE and will be a useful adjunct to manuals that describe experimental PFGE procedures.

NANCY C. STELLWACEN

University of Iowa

electroporation and electrofusion. The chapters are not written as “how to,” but instead discuss the advantages of using electroporation or electrofusion in specific circumstances. These cover electropora- tion of DNA into bacteria, yeast, plant protoplasts, and tissue culture cells, as well as electroporation of proteins into cells. There are also chapters on electrofusion in the formation of monoclonal antibodies, in the production of genetically identical embryos by electroporation, and in cell-tissue electrofusions. In many cases there are independent chapters on roughly the same topic that present slightly different approaches or reasons for using the procedures. Although this results in some redundancy in the text, it is largely a positive factor in that it presents different viewpoints on a single question. The final chapter of this section is entitled Novel Applications of Electroporation. This

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