Oscar Juarez

  • Associate Professor of Biology


Ph.D. National University of Mexico
B.S. National University of Mexico

Research Interests

Our lab conducts biomedical research directed to establish the metabolic strategies and host- pathogen relationship in bacterial pathogenic species, such as Chlamydia trachomatis, the most prevalent sexually transmitted disease in the world, and Vibrio cholerae, which produces severe gastrointestinal disease to millions of people in developing countries.

Our research uses an interdisciplinary approach to study these topics, with diverse methodologies, such as molecular and structural biology, protein chemistry and cell biology. This strategy allows us to characterize the behavior of enzymes and understand molecular and subatomic aspects, such as electron movement and conformational changes, and apply these concepts to cell to cell relationships, disease development and drug design.


Peer-reviewed publications

  • Raba DA, Rosas-Lemus M, Menzer WM, Li C, Fang X, Liang P, Tuz K, Minh DDL, Juarez O (2018) Characterization of the Pseudomonas aeruginosa NQR Complex, a Bacterial Proton Pump with Roles in Autopoisoning Resistance. J. Biol. Chem. 2018. In press. doi: 10.1074/jbc.RA118.003194
  • Veseli IA, Mascarenhas dos Santos AC, Juárez O, Stark BC, Pombert JF (2018) Complete genome sequence of Vitreoscilla sp. strain C1, source of the first bacterial hemoglobin Microbiol Resour Announc. 2018. 7:e00922-18. DOI: 10.1128/MRA.00922-18
  • Liang P, Rosas-Lemus M, Patel D, Fang X, Tuz K, Juárez O (2017) Dynamic Energy Dependency of Chlamydia trachomatis on Host Cell Metabolism during Different Stages of Intracellular Growth: Possible role of Sodium -based energetics in Chlamydial ATP generation. J. Biol. Chem. 2018 293:510-. DOI: 10.1074/jbc.M117.797209
  • Fang X, Liang P, Raba DA, Rosas-Lemus M, Chakravarthy S, Tuz K, Juárez O (2017) Kinetic characterization of Vibrio cholerae ApbE: Substrate specificity and regulatory mechanisms. PLoS One. 2017 Oct 24;12(10):e0186805. DOI: 10.1371/journal.pone.0186805
  • Tuz K, Li C, Fang X, Raba DA, Liang P, Minh DD, Juarez O (2017) Identification of the catalytic ubiquinone-binding site of Vibrio cholerae sodium-dependent NADH dehydrogenase: a novel ubiquinone-binding motif. J Biol Chem. 2017 Feb 17;292(7):3039-3048. DOI: 10.1074/jbc.M116.770982
  • Tuz K, Mezic KG, Xu T, Barquera B, Juarez O (2016) The kinetic reaction mechanism of the Vibrio cholerae sodium-dependent NADH dehydrogenase. J Biol Chem. 2015. 290(33):20009-200021. PMID: 26004776, PMCID: PMC4536408
  • Hreha TN, Mezic KG, Herce HD, Duffy EB, Bourges A, Pryshchep S, Juárez O, Barquera B (2016) Complete topology of the RNF complex from Vibrio cholerae. Biochemistry. 2015. 54(15):2443-2455. PMID: 25831459
  • Shea ME, Mezic KG, Juárez O, Barquera B. (2015) A Mutation in Na+-NQR Uncouples Electron Flow from Na+ Translocation in the Presence of K+. Biochemistry. 54(2):490-6
  • Strickland M, Juárez O, Neehaul Y, Cook DA, Barquera B, Hellwig P. (2014) The conformational changes induced by ubiquinone binding in the Na+-pumping NADH:ubiquinone oxidoreductase (Na+-NQR) are kinetically controlled by conserved glycines 140 and 141 of the NqrB subunit. J Biol Chem. 289(34):23723-33
  • Reyes-Prieto A, Barquera B, Juárez O. (2014) Origin and evolution of the sodium -pumping NADH: ubiquinone oxidoreductase. PLoS One. 9(5):e96696.
  • Shea ME, Juárez O, Cho J, Barquera B. (2013) Aspartic acid 397 in subunit B of the Na+-pumping NADH:quinone oxidoreductase from Vibrio cholerae forms part of a sodium-binding site, is involved in cation selectivity, and affects cation-binding site cooperativity. J Biol Chem. 288(43):31241-9.
  • Neehaul Y, Juárez O, Barquera B, Hellwig P. (2013) IR spectroscopic evidence for a redox -dependent conformational change involving ion binding residue NqrB-D397 in the Na+ pumping NADH:quinone oxidoreductase from Vibrio cholerae. Biochemistry. 52(18):3085-93
  • Juárez O, Barquera B. (2012) Insights into the mechanism of electron transfer and sodium translocation of the Na+-pumping NADH:quinone oxidoreductase. Biochim Biophys Acta. 1817(10):1823-32
  • Tuz K, Hsiao YC, Juárez O, Shi B, Harmon EY, Phelps IG, Lennartz MR, Glass IA, Doherty D, Ferland RJ. (2013) The Joubert Syndrome Associated Missense Mutation (V443D) in the Abelson-helper Integration Site 1 (AHI1) Protein Alters Its Localization and Protein-Protein Interactions. J Biol Chem. 288(19):13676-94.
  • Juárez O, Barquera B. (2012) Insights into the mechanism of electron transfer and sodium translocation of the Na+-pumping NADH:quinone oxidoreductase. Biochim Biophys Acta. 1817(10):1823-32
  • Juárez O, Neehaul Y, Turk E, Chaubon N, Hellwig P and Barquera B. (2012) The role of Glycine residues 140 and 141 of NqrB subunit in the ubiquinone binding site of the sodium -dependent NADH dehydrogenase. J Biol Chem. 287(30):25678-85
  • Neehaul Y, Juárez O, Barquera B, Hellwig P. (2012) Thermodynamic Contribution to the Regulation of Electron Transfer in the Na+-Pumping NADH:Quinone Oxidoreductase from Vibrio cholerae. Biochemistry. 51 (19): 4072–4077
  • Juárez O, Shea ME, Makhatadze GI, Barquera B. (2011) The Role and Specificity of the Catalytic and Regulatory Cation-binding Sites of the Na+-pumping NADH:Quinone Oxidoreductase from Vibrio cholerae. J Biol Chem. 286(30):26383-90.
  • De Los Rios Castillo D, Zarco-Zavala M, Olvera-Sanchez S, Pardo JP, Juárez O, Martinez F, Mendoza-Hernandez G, García-Trejo JJ, Flores-Herrera O. (2011) Atypical Cristae Morphology of Human Syncytiotrophoblast Mitochondria: Role of Complex V. J Biol Chem. 286(27):23911-9.
  • Juárez O, Morgan JE, Nilges M, Barquera B. (2010) The energy transducing redox steps of the Na+-NQR from Vibrio cholerae. Proc. Natl. Acad. Sci. 107(28):12505-10.
  • Juárez O, Athearn K, Gillespie P, Barquera B (2009) Acid residues involved in the sodium translocation mechanism of Na+-NQR. Biochemistry. 48(40):9516-24.
  • Juárez O, Morgan JE, Barquera B (2009) The electron transfer pathway of the Na+-pumping NADH:quinone oxidoreductase from Vibrio cholerae. J. Biol. Chem. 284(13):8963-72.
  • Juárez O, Nilges MJ, Gillespie P, Cotton J, Barquera B (2008). Riboflavin is an active redox cofactor in the Na+-pumping NADH: quinone oxidoreductase (Na+-NQR) from Vibrio cholerae. J. Biol. Chem. 283(48):33162-7.
  • Backiel J, Juárez O, Zagorevski DV, Wang Z, Nilges MJ, Barquera B (2008) Covalent binding of flavins to RnfG and RnfD in the Rnf complex from Vibrio cholerae. Biochemistry 47(43):11273-84.
  • Guevara-Flores A, Olvera-Sánchez S, Gómez-Concha C, Juárez O, Esparza-Perusquía M, Pardo JP, Mendoza-Hernández G, Martínez F, Flores-Herrera O (2008) 5'-p-Fluorosulfonyl benzoyl adenosine inhibits an ecto-ATP-diphosphohydrolase in the tegument surface of Taenia crassiceps cysticerci. Mol Biochem Parasitol. 162(2):123-33.
  • Juárez O, Guerra G, Velázquez I, Flores-Herrera O, Rivera-Pérez RE, Pardo JP (2006) The physiologic role of alternative oxidase in Ustilago maydis. FEBS J. 273(20):4603-15.
  • Juárez O, Guerra G, Martínez F, Pardo JP (2004) The mitochondrial respiratory chain of Ustilago maydis. Biochim Biophys Acta. 1658(3):244-51.

Book chapters

  • Juarez O, Barquera B. (2010) Sodium pumping NADH dehydrogenase. In: Biochemical Communication (Ed. Vazquez-Meza), Mexico City, UNAM, p. 116.
  • Juárez O, Pardo JP. Structure and function of the alternative oxidase. In: Advances in Protein Physical Chemistry (Ed. Fernandez-Velasco A), Kerala, Research Signpost, p. 303.
  • Rendón JL, Juárez O (2009) Glutathione reductase: Structural, catalytic and functional aspects. In: Advances in Protein Physical Chemistry (Ed. Fernandez-Velasco A), Kerala, Research Signpost, p. 317.


  1. Studies of the metabolic adaptations and host- pathogen relationship of pathogenic bacteria
  2. Structural and functional analysis of enzymes and proteins involved in ion homeostasis and energy production
  3. Rational design of drugs against pathogenic bacteria


Mechanistic enzymology, metabolic network characterization, and protein chemistry