Neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS) lack robust diagnostics and prognostic biomarkers. Metabolomics is a postgenomics field that offers fresh insights for biomarkers of common complex as well as rare diseases. Using data on metabolite-disease associations published in the previous decade (2006-2016) in PubMed, ScienceDirect, Scopus, and Web of Science, we identified 101 metabolites as putative biomarkers for these three neurodegenerative diseases. Notably, uric acid, choline, creatine, L-glutamine, alanine, creatinine, and N-acetyl-L-aspartate were the shared metabolite signatures among the three diseases. The disease-metabolite-pathway associations pointed out the importance of membrane transport (through ATP binding cassette transporters), particularly of arginine and proline amino acids in all three neurodegenerative diseases. When disease-specific and common metabolic pathways were queried by using the pathway enrichment analyses, we found that alanine, aspartate, glutamate, and purine metabolism might act as alternative pathways to overcome inadequate glucose supply and energy crisis in neurodegeneration. These observations underscore the importance of metabolite-based biomarker research in deciphering the elusive pathophysiology of neurodegenerative diseases. Future research investments in metabolomics of complex diseases might provide new insights on AD, PD, and ALS that continue to place a significant burden on global health.

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An extracellular serine alkaline protease of Bacillus clausii GMBAE 42 was produced in protein-rich medium in shake-flask cultures for 3 days at pH 10.5 and 37 degrees C. Highest alkaline protease activity was observed in the late stationary phase of cell cultivation. The enzyme was purified 16-fold from culture filtrate by DEAE-cellulose chromatography followed by (NH(4))(2)SO(4) precipitation, with a yield of 58%. SDS-PAGE analysis revealed the molecular weight of the enzyme to be 26.50 kDa. The optimum temperature for enzyme activity was 60 degrees C; however, it is shifted to 70 degrees C after addition of 5 mM Ca(2+) ions. The enzyme was stable between 30 and 40 degrees C for 2 h at pH 10.5; only 14% activity loss was observed at 50 degrees C. The optimal pH of the enzyme was 11.3. The enzyme was also stable in the pH 9.0--12.2 range for 24 h at 30 degrees C; however, activity losses of 38% and 76% were observed at pH values of 12.7 and 13.0, respectively. The activation energy of Hammarsten casein hydrolysis by the purified enzyme was 10.59 kcal mol(-1) (44.30 kJ mol(-1)). The enzyme was stable in the presence of the 1% (w/v) Tween-20, Tween-40,Tween-60, Tween-80, and 0.2% (w/v) SDS for 1 h at 30 degrees C and pH 10.5. Only 10% activity loss was observed with 1% sodium perborate under the same conditions. The enzyme was not inhibited by iodoacetate, ethylacetimidate, phenylglyoxal, iodoacetimidate, n-ethylmaleimidate, n-bromosuccinimide, diethylpyrocarbonate or n-ethyl-5-phenyl-iso-xazolium-3'-sulfonate. Its complete inhibition by phenylmethanesulfonylfluoride and relatively high k (cat) value for N-Suc-Ala-Ala-Pro-Phe-pNA hydrolysis indicates that the enzyme is a chymotrypsin-like serine protease. K (m) and k (cat) values were estimated at 0.655 microM N-Suc-Ala-Ala-Pro-Phe-pNA and 4.21 x 10(3) min(-1), respectively.

Four Gram-negative, moderately halophilic, exopolysaccharide-producing strains, designated AAD6 T , AAD4, AAD17 and AAD21, were isolated from Ç amaltı Saltern Area, a wildlife reserve in Sasalı, I˙zmir province located in the Aegean Region of Turkey. The isolates grew at an optimum NaCl concentration of 10 % (w/v). The major cellular fatty acids were C 16 : 0 , C 18 : 1 v7c, C 16 : 1 v7c and C 12 : 0 3OH, respectively and the predominant lipoquinone was ubiquinone Q-9. The G+C content of the genomic DNA of strains AAD6