دورية أكاديمية

Cysteine Metallochemistry and Metal Binding: Quantification of the Thermodynamic Foundations of Cellular Homeostasis

التفاصيل البيبلوغرافية
العنوان: Cysteine Metallochemistry and Metal Binding: Quantification of the Thermodynamic Foundations of Cellular Homeostasis
المؤلفون: Mehlenbacher, Matthew R
المصدر: Dartmouth College Ph.D Dissertations
بيانات النشر: Dartmouth Digital Commons
سنة النشر: 2022
المجموعة: Dartmouth Digital Commons (Dartmouth College)
مصطلحات موضوعية: Thermodynamics, Metalloproteins, Mercury, MerR, Copper Storage Proteins, Metallothionein, Metal-Binding, Enthalpy, Metals, Biochemistry, Inorganic Chemistry
الوصف: Metals are required for life. Many metalloproteins contain cysteine in their metal-binding site (MBS) and cysteines are unique in that they are reactive, and strongly bind certain metals, which aid in metal selectivity and specificity. Using isothermal titration calorimetry (ITC), the thermodynamic foundation for metal binding, cellular protection, and transcriptional regulation, which all utilize cysteines in their MBS, are quantified. In bacteria there are metalloprotein pathways that actively uptake mercury, which are regulated by the metalloregulatory protein MerR. MerR de-represses the transcription of these mer proteins in a metal-dependent manner. Using ITC, the thermodynamic foundation of the negative allosteric coupling that regulates MerR is quantified. Within this regulated pathway is a metallochaperone in the periplasm of the cell, MerP, which functions as a mercury buffer, protecting the cell from the deleterious effects of the metal. The thermodynamic foundation of cellular protection and the mechanism of metal binding is characterized. MerP is a part of a class of metallochaperones that all contain the same protein architecture and MBS. However, this class of metallochaperones binds a wide range of metals, including zinc, copper, and mercury. How one protein scaffold with the same MBS modulates metal binding is unknown. The fundamental thermodynamics suggest that second-sphere interactions are capable of modulating metal-binding properties of these ferredoxin-like folded proteins leading to metal selectivity and specificity. Unlike bacterial mer protein, which generally bind one metal ion, other cysteine-rich proteins bind multiple metals simultaneously. In this work, the thermodynamics and mechanism of copper and zinc binding to human metallothionein (MT), a protein with many cellular functions in the regulation of metal toxicity and neuron growth inhibition, were quantified. The binding of copper, zinc, and mercury to bacterial copper storage proteins (CSPs), which also utilize a large number of ...
نوع الوثيقة: text
وصف الملف: application/pdf
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العلاقة: https://digitalcommons.dartmouth.edu/dissertations/100Test; https://digitalcommons.dartmouth.edu/context/dissertations/article/1102/viewcontent/Mehlenbacher_PhD_Thesis_2022_Not_Signed.pdfTest
الإتاحة: https://digitalcommons.dartmouth.edu/dissertations/100Test
https://digitalcommons.dartmouth.edu/context/dissertations/article/1102/viewcontent/Mehlenbacher_PhD_Thesis_2022_Not_Signed.pdfTest
رقم الانضمام: edsbas.26C10F7F
قاعدة البيانات: BASE