Description: Background: Halotolerant bacteria are excellent sources for selecting novel enzymes. Being intrinsically stable and active under high salinities, enzymes from these prokaryotes have evolved to function optimally under extreme conditions, making them robust biocatalysts with potential applications in harsh industrial processes. Results: A halotolerant strain LY19 showing lipolytic activity was isolated from saline soil of Yuncheng Salt Lake, China. It was identified as belonging to the genus of Salimicrobium by 16S rRNA gene sequence analysis. The extracellular enzyme was purified to homogeneity with molecular mass of 57 kDa by SDS-PAGE. Substrate specificity test revealed that the enzyme preferred short-chain p-nitrophenyl esters and exhibited maximum activity towards p-nitrophenyl butyrate (p-NPB), indicating an esterase activity. The esterase was highly active and stable over broad temperature (20[degree sign]C-70[degree sign]C), pH (7.0-10.0) and NaCl concentration (2.5%-25%) ranges, with an optimum at 50[degree sign]C, pH 7.0 and 5% NaCl. Significant inhibition of the esterase was shown by ethylenediaminetetraacetic acid (EDTA), phenylmethylsulfonyl fluoride (PMSF) and phenylarsine oxide (PAO), which indicated that it was a metalloenzyme with serine and cysteine residues essential for enzyme activity. Moreover, the esterase displayed high activity and stability in the presence of hydrophobic organic solvents with log Pow 〉= 0.88 than in the absence of an organic solvent or in the presence of hydrophilic solvents. Conclusions: Results from the present study indicated the novel extracellular esterase from Salimicrobium sp. LY19 exhibited thermostable, alkali-stable, halotolerant and organic solvent-tolerant properties. These features led us to conclude that the esterase may have considerable potential for industrial applications in organic synthesis reactions.

Description: Background: Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism, which leads to the accumulation of this metal in liver, brain, cornea and kidney. Little is reported about spinal deformity associated with this syndrome. This study is to present a case of thoracic kyphosis occurring in the setting of Wilson'disease and explore the possible association between the two diseases.Case presentationCase report and literature review. A previously unreported thoracic kyphosis in Wislon's disease is decribed. The patient was a 7-year-old Chinese female that underwent a posterior correction, using the Moss-SI spinal system performed at Thoracic 9-Lumbar 1 (T9-L1) levels. At 16-month follow-up, the patient was clinically pain free and well balanced. Plain radiographs showed solid spine fusion with no loss of deformity correction. After evaluating 211 WD patients referred to Peking Union Medical College Hospital from February 1991 to February 2012, the prevalence of congential scoliosis among patients with WD was 5.21% (11/211), much higher than that among general population (1/1000). Conclusions: To the best of our knowledge, this is the first report of WD with thoracic kyphosis. During sugery, surgeons and anesthesiologists must pay particular attention to the abnormal liver and brain function associated with WD. The prevalence of scoliosis is much higher among patients with WD, indicating a potential association between congential scoliosis and WD. However, the exact mechanism how copper-chelating agents induce scoliosis is unclear.