Quantitation of nucleoprotein complexes by UV absorbance and Bradford assay

Jiang Chen; Hao Luo; Mei Tao; Zhongchuan Liu; Ganggang Wang

doi:10.52601/bpr.2021.210028

Volume 7 Issue 6

Dec. 2021

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Jiang Chen, Hao Luo, Mei Tao, Zhongchuan Liu, Ganggang Wang. Quantitation of nucleoprotein complexes by UV absorbance and Bradford assay[J]. Biophysics Reports, 2021, 7(6): 429-436. doi: 10.52601/bpr.2021.210028

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Jiang Chen, Hao Luo, Mei Tao, Zhongchuan Liu, Ganggang Wang. Quantitation of nucleoprotein complexes by UV absorbance and Bradford assay[J]. Biophysics Reports, 2021, 7(6): 429-436. doi: 10.52601/bpr.2021.210028

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Quantitation of nucleoprotein complexes by UV absorbance and Bradford assay

doi: 10.52601/bpr.2021.210028

Jiang Chen^{1, 2, 3},
Hao Luo^{1, 3},
Mei Tao¹,
Zhongchuan Liu¹,
Ganggang Wang^{1
,
,}

1.
Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences; Key Laboratory of Environmental Microbiology of Sichuan Province, Chengdu 610041, China
2.
College of Life Sciences, Sichuan University, Chengdu 610064, China
3.
University of Chinese Academy of Sciences, Beijing 100049, China

Funds: This work was supported by grants from the National Natural Science Foundation of China (31470742, 31700664, U1432102, 31270783), an initial grant from the 100 Talents Program of the Chinese Academy of Sciences, and the Key Laboratory of Environmental and Applied Microbiology at the Chinese Academy of Sciences. We thank Dr. Aparicio for the gift of the Fhk1-DBD plasmid.

More Information

Corresponding author: wanggg@cib.ac.cn (G. Wang)
Received Date: 27 July 2021
Accepted Date: 26 November 2021

Available Online: 28 February 2022

Publish Date: 31 December 2021

Abstract

Abstract

Despite the importance of studying nucleoprotein complexes, no appropriate method for quantifying them is available. Here, a UV absorbance method using the formula “C_mg/mL = 1.55A₂₈₀ – 0.76A₂₆₀” were applied to quantify nucleoprotein complexes. After modification using two paired A₂₆₀ and A₂₈₀ values, the UV-derived formula-based method could accurately quantify proteins in nucleoprotein complexes. Otherwise, by taking the target protein as a standard, the Bradford assay can accurately quantify proteins in nucleoprotein complexes without interference by nucleic acids. The above methods were successfully applied to measure the concentration of MtuP49-CTG complexes of Mycobacterium tuberculosis. In conclusion, both the Bradford assay and the UV-derived formula-based method were appropriate for quantifying proteins in nucleoprotein complexes, which may make contributions to explore the interactions between proteins and nucleic acids at the molecular level.
- Nucleoprotein complex,
- Quantitation,
- Bradford assay,
- UV-derived formula-based method

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References(16)

References

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