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Overview: What Are Helicases?

Chapter
First Online:
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 767)

Abstract

First discovered in the 1970s, DNA helicases were initially described as enzymes that use chemical energy to separate (i.e., to unwind) the complementary strands of DNA. Because helicases are ubiquitous, display a range of fascinating biochemical activities, and are involved in all aspects of DNA metabolism, defects in human helicases are linked to a variety of genetic disorders, and helicase research continues to be important in understanding the molecular basis of DNA replication, recombination, and repair. The purpose of this book is to organize this information and to update the traditional view of these enzymes, because it is now evident that not all helicases possess bona fide strand separation activity and may function instead as energy-dependent switches or translocases. In this chapter, we will first discuss the biochemical and structural features of DNA—the lattice on which helicases operate—and its cellular organization. We will then provide a historical overview of helicases, starting from their discovery and classification, leading to their structures, mechanisms, and biomedical significance. Finally, we will highlight several key advances and developments in helicase research, and summarize some remaining questions and active areas of investigation. The subsequent chapters will discuss these topics and others in greater detail and are written by experts of these respective fields.

Keywords

Forster Resonance Energy Transfer Helicase Activity Optical Trap Forster Resonance Energy Transfer Efficiency Strand Separation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of BiochemistryUniversity of Iowa Carver College of MedicineIowa CityUSA

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