Enhancement of Lysozyme Crystallization Using DNA as a Polymeric Additive

Yao Wang,Shilong Fan,Lijin Xu,Bo Zhang,Ping Luo,Jerry Heng,Zhongqiang Yang,Shiki Thi,Vincent Toong

doi:10.3390/cryst9040186

Yao Wang, Shilong Fan + Show 7 more

Open Access

https://doi.org/10.3390/cryst9040186

Copy DOI

Abstract

This study reports the first experimental evidence of using DNA as a polymeric additive to enhance protein crystallization. Using three kinds of DNA with different molecular weights—calf DNA, salmon DNA, and herring DNA—this study showed an improvement in the success rate of lysozyme crystallization, as compared to control experiments, especially at low lysozyme concentration. The improvement of crystallization is particularly significant in the presence of calf DNA with the highest molecular weight. Calf DNA also speeds up the induction time of lysozyme crystallization and increases the number of crystals per drop. We hypothesized the effect of DNA on protein crystallization may be due to the combination of excluded volume effect, change of water’s surface tension, and the water competition effect. This work confirms predications of the potential use of DNA as a polymeric additive to enhance protein crystallization, potentially applied to systems with limited protein available or difficult to crystallize.

Highlights

Deoxyribonucleic acid (DNA) is a molecule that consists of nitrogen-containing nucleobases and a sugar phosphate
We conducted a series of experiments to explore if the addition of DNA as a polymeric additive has a positive effect on protein crystallization
We presented for the first time using DNA as a new kind of polymeric additive to

Summary

Introduction

Deoxyribonucleic acid (DNA) is a molecule that consists of nitrogen-containing nucleobases and a sugar phosphate. DNA has been utilized as chemical materials and scientists have been trying to endue DNA more new properties by modifying DNA with a variety of functional molecules [4]. The DNA molecule has extraordinary characteristics which include precise recognition and the DNA sequences can be programed and designed into different kinds of nanostructures such as DNA origami [5,6,7,8,9,10,11,12,13]. We have already found that DNA origami can be applied to enhance protein crystallization [14]. This precisely designable and programmable nanostructure is an effective material in the field of protein crystallization. Intrinsic polymeric property has been neglected in protein crystallization

Methods

Results

Conclusion