40. Epstein W, Kim BS: Potassium transport loci in Escherichia coli K-12. J Bacteriol 1971, 108:639–644.PubMed 41. Ho SN, Hunt HD, Horton RM, Pullen JK, Pease LR: Site-directed mutagenesis by overlap extension using the polymerase

chain reaction. Gene 1989, 77:51–59.PubMedCrossRef 42. Laemmli UK: Cleavage of structural proteins during the assembly of the head of bacteriophage T4. QNZ research buy Nature 1970, 227:680–685.PubMedCrossRef 43. Miller JH: Experiments in molecular genetics. In A short course in bacterial genetics. Edited by: Miller JH. Cold Spring Habor, selleck NY: Cold Spring Harbor Laboratory Press; 1992:72–74. 44. Lemonnier M, Lane D: Expression of the second lysine decarboxylase gene of Escherichia coli . Microbiology 1998,144(Pt 3):751–760.PubMedCrossRef 45. Heermann R, Weber A, Mayer B, Ott M, Hauser E, Gabriel G, et al.: The universal stress protein

UspC scaffolds the KdpD/KdpE signaling cascade of Escherichia click here coli under salt stress. J Mol Biol 2009, 386:134–148.PubMedCrossRef 46. Studier FW, Moffatt BA: Use of bacteriophage T7 RNA polymerase to direct selective high-level expression of cloned genes. J Mol Biol 1986, 189:113–130.PubMedCrossRef 47. Blattner FR, Plunkett G III, Bloch CA, Perna NT, Burland V, Riley M, et al.: The complete genome sequence of Escherichia coli K-12. Science 1997, 277:1453–1474.PubMedCrossRef 48. Guzman LM, Belin D, Carson MJ, Beckwith J: Tight regulation, modulation, and high-level expression Ribonuclease T1 by vectors containing the arabinose P BAD promoter. J Bacteriol 1995, 177:4121–4130.PubMed Authors’ contributions LT, CK and KJ designed research experiments; AD performed experiments; LT performed experiments and

analyzed data. LT and KJ wrote the manuscript. All authors have read and approved the final manuscript.”
“Background Coccidioides immitis and posadasii are pathogenic fungi that grow in the arid soils of the southwestern United States, Mexico and Central and South America. Mycelia in the soil give rise to infectious arthroconidia, which, when aerosolized, can be inhaled. The severity of coccidioidomycois (Valley Fever) ranges from a mild self-limited disease to a severe pneumonia and widely disseminated infection requiring lifelong antifungal therapy [1]. The risk factors for the more severe forms of disease include ethnic background (Filipino, African-American, Hispanic), male sex, increasing age, pregnancy and immunosuppression (HIV, malignancy, organ transplantation) [2–4]. The role of polymorphonuclear leukocytes (PMNs) macrophages and the oxidative burst in the defense against Coccidioides is not clearly defined. PMN’s are the first cell to respond to inhaled arthroconidia [5]. Although arthroconidia are sensitive to products of the oxidative burst [6, 7] and are phagocytosed by PMNs [8–10], fewer than 20% of arthroconidia are killed by human PMNs [8, 9, 11, 7].