The Extended Loop Reduces Ca2+-Binding Affinity on the Tellurite Resistance Protein TerZ from Klebsiella penumoniae

doi:10.11938/cjmr20150213

Abstract

Abstract:

Tellurite (TeO₃^2–), an oxyanion of tellurium, is highly toxic to most microorganisms. Several tellurite resistance genes (terZABCDEF) have been identified in many pathogenic bacteria. Previously, we determined the NMR solution structure of the tellurite resistance protein TerD and suggested that TerD may function as a calcium sensor in bacteria. TerZ, which shares 40% sequence identity with TerD, contains an extra 9-residue segment of L36FGSIFGGN44 and exhibits much weaker Ca²⁺-binding affinity. Interestingly, TerZdel in which the extra segment is deleted has comparable binding affinity to TerD. Based on chemical shift index and homology modeling results, it was revealed that the extra segment is unstructured and forms an extended loop, which may disturb the conformation of Ca2+-binding sites and also prevent Ca²⁺ from contacting its binding site, hence significantly reduce Ca²⁺-binding affinity.

Key words: Ca²⁺-binding protein, tellurite resistance, calcium sensor, chemical shift index, homology modeling

CLC Number:

O482.53

WEI Shu-yi, PAN Yun-ru, TSENG Tien-sheng, CHEN Chin-pan?. The Extended Loop Reduces Ca2+-Binding Affinity on the Tellurite Resistance Protein TerZ from Klebsiella penumoniae[J]. Chinese Journal of Magnetic Resonance, 2015, 32(2): 308-317.

References

[1] Taylor D E. Bacterial tellurite resistance[J]. Trends Microbiol, 1999, 7(3): 111－115.

[2] Chasteen T G, Fuentes D E, Tantalean J C, et al. Tellurite: history, oxidative stress, and molecular mechanisms of resistance[J]. FEMS Microbiol Rev, 2009, 33(4): 820－832.

[3] Walter E G, Taylor D E. Plasmid-mediated resistance to tellurite: expressed and cryptic[J]. Plasmid, 1992, 27(1): 52－64.

[4] Chen Y T, Chang H Y, Lai Y C, et al. Sequencing and analysis of the large virulence plasmid pLVPK of Klebsiella pneumoniae CG43[J]. Gene, 2004, 337: 189－198.

[5] Whelan K F, Colleran E, Taylor D E. Phage inhibition, colicin resistance, and tellurite resistance are encoded by a single cluster of genes on the IncHI2 plasmid R478[J]. J Bacteriol, 1995, 177(17): 5 016－5 027.

[6] Valkovicova L, Vavrova S M, Mravec J, et al. Protein-protein association and cellular localization of four essential gene products encoded by tellurite resistance-conferring cluster “ter” from pathogenic Escherichia coli[J]. Antonie Van Leeuwenhoek, 2013, 104(6): 899－911.

[7] Anantharaman V, Iyer L M, Aravind L. Ter-dependent stress response systems: novel pathways related to metal sensing, production of a nucleoside-like metabolite, and DNA-processing[J]. Mol Biosyst, 2012, 8(12): 3 142－3 165.

[8] Pan Y R, Lou Y C, Seven A B, et al. NMR structure and calcium-binding properties of the tellurite resistance protein TerD from Klebsiella pneumoniae[J]. J Mol Biol, 2011, 405(5): 1 188－1 201.

[9] Pan Y R. Structure as a Guide to Function: NMR Studies on Tellurite Resistance Proteins from Klebsiella pneumoniae[D]. Hsinchu: Institute of Bioinformatics and Structural Biology, College of Life Science, “National Tsing Hua University”, 2011.

[10] Wu K M, Li L H, Yan J J, et al. Genome sequencing and comparative analysis of Klebsiella pneumoniae NTUH-K2044, a strain causing liver abscess and meningitis[J]. J Bacteriol, 2009, 191(14): 4 492－4 501.

[11] Schuck P. Size-distribution analysis of macromolecules by sedimentation velocity ultracentrifugation and lamm equation modeling[J]. Biophys J, 2000, 78(3): 1 606－1 619.

[12] Delaglio F, Grzesiek S, Vuister G W, et al. NMRPipe: a multidimensional spectral processing system based on UNIX pipes[J]. J Biomol NMR, 1995, 6(3): 277－293.

[13] Johnson B A, Blevins R A. NMR View: A computer program for the visualization and analysis of NMR data[J]. J Biomol NMR, 1994, 4(5): 603－614.

[14] Biasini M, Bienert S, Waterhouse A, et al. SWISS-MODEL: modelling protein tertiary and quaternary structure using evolutionary information[J]. Nucleic Acids Res, 2014, 42(W1): W252－W258.

[15] Sali A, Blundell T L. Comparative protein modelling by satisfaction of spatial restraints[J]. J Mol Biol, 1993, 234(3): 779－815.

[16] Morris A L, MacArthur M W, Hutchinson E G., et al. Stereochemical quality of protein structure coordinates[J]. Proteins, 1992, 12(4): 345－364.

[17] Laskowski R A, Macarthur M W, Moss D S, et al. Procheck: a program to check the stereochemical quality of protein structures[J]. J Appl Cryst, 1993, 26(0), 283－291.

[18] Shen Y, Bax A. Protein backbone and sidechain torsion angles predicted from NMR chemical shifts using artificial neural networks[J]. J Biomol NMR, 2013, 56(3): 227－241.