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A novel, cellulolytic, bacterial thermophilic strain, T4, was isolated from sugar refinery wastewater in southern Taiwan. This isolate, a Gram-negative, motile, aerobically growing sporulating rod, can secrete thermostable endocellulase (endo-1,4-ß-D-glucanase, EC 3.2.1.4) and hydrolyze carboxymethylcellulose (CMC), phosphoric acid-swollen cellulose, Avicel, filter paper, and salicin. When strain T4 was grown in CMC medium, the cellulolytic enzyme activity in culture supernatants was stable up to 70°C. More than 10% of the original activity was still detectable after heating to 100°C with a pH 7.0 for 1 h. Based on 16S rDNA sequence analysis, DNA base composition, phenotypic and physiological characteristics, as well as DNA-DNA hybridization, strain T4 was classified asGeobacillus thermoleovoransT4 (DSM 14791 = CCRC 17200). We also demonstrated that the type speciesG. stearothermophilus(DSM 22 = ATCC 12980) could hydrolyze amorphous and crystalline (filter paper) celluloses at a rate of 13 and 14%, respectively, in comparison with strain T4. [ABSTRACT FROM AUTHOR]

Motile cells of the unicellular red alga, Porphyridium purpureum (Bory) Drew & Ross were studied using light, interference, and electron microscopy. In liquid culture, moving cells possessed a mucilaginous stalk which extended from one end of the cell and tapered to a point. On an agar surface, distinct trails were left by moving cells. With interference microscopy, the trails appeared to be shallow grooves. Microscopy of shadowed replicas confirmed that moving cells produced a shallow groove as they moved across agar. Ultrastructure observations revealed that cells moving on agar exhibited morphological polarity. Large vesicular elements containing fibrillar material similar to that in the cellular sheath was associated with the posterior area of the motile cells. [ABSTRACT FROM AUTHOR]

The NADP-specific glutamate dehydrogenase (GDH) from Escherichia coli strain DHG, an enzyme that catalyzes the interconversion of α-ketoglutarate and l-glutamate, has been shown to be phosphorylated in vitro in an ATP-dependent enzymatic reaction. The phosphorylated protein is extremely acid labile and is unstable at high pH. Treatment of GDH with diethyl pyrocarbonate (DEP), a histidine-modifying reagent, blocked the incorporation ofP from [γ-P]ATP. GDH catalytic activity was also inhibited by DEP treatment. Hydroxylamine, a reagent hydrolyzing phosphoramidates, catalyzed the removal of phosphate from phosphorylated GDH, suggesting that GDH may be phosphorylated at a histidine residue(s). A total enzymatic hydrolysis of phosphorylated GDH, which was electroeluted from a native polyacrylamide gel, was analyzed by a Dowex 1-8X anion exchange chromatography. The presence ofP-labeled 3-phosphohistidine, characterized and identified from this hydrolysate, demonstrates that a histidine residue(s) is the site of phosphorylation. [ABSTRACT FROM AUTHOR]

The NADP-specific glutamate dehydrogenase from Escherichia coli has been purified to electrophoretic homogeneity. The enzyme was purified 40-fold and has a specific activity of 23. Glutamate dehydrogenase from E. coli is a hexameric enzyme with a native molecular weight of 275 KDa composed of monomers each with a molecular weight of 44.5 KDa. In nondenaturing isoelectric focusing gels, the purified enzyme is resolved into six catalytically active species, each with a molecular weight of 275 KDa and with isoelectric points ranging between pH 5.3 and 5.7. The K values for substrates and coenzymes have been determined, and the effect of several divalent ions on catalytic activity has been investigated. [ABSTRACT FROM AUTHOR]

Glutamate dehydrogenase from Escherichia coli is phosphorylated in vitro in an ATP-dependent enzymatic reaction. The phosphorylated protein, when exposed to acid conditions, releases the phosphate; this implies that the phosphorylation site is not on a serine, tyrosine, or threonine residue(s). Treatment of glutamate dehydrogenase with diethyl pyrocarbonate, a highly specific histidine-modifying reagent, blocks incorporation ofP-phosphate from [ γ-P]ATP into the enzyme, suggestive that the phosphorylation site is a histidine residue(s). The phosphorylated glutamate dehydrogenase was identified on the basis of its comigration with highly purified glutamate dehydrogenase, isolated from E. coli, on denaturing, nondenaturing, and isoelectric focusing polyacrylamide gels and by sequence analysis. [ABSTRACT FROM AUTHOR]

The sex chromosome bivalent was examined in Drosophila melanogaster males possessing the In(1)scsc X chromosome. Three-dimensional reconstructions from electron micrographs of serially cut thin sections were made. A large proportion of the kinetochores of In(1)scsc/Y bivalents did not face opposite poles during metaphase I and anaphase I. This suggests that In(1)scsc/Y bivalents may have difficulty achieving bipolar stability. Delay in achieving bipolar stability could contribute to the nondisjunctional behavior found in In(1)scsc/Y males. [ABSTRACT FROM AUTHOR]

The NADP-specific glutamate dehydrogenase in Escherichia coli K12 has been shown to be phosphorylated in vivo when the cells are grown in a low-phosphate minimal salts medium containingP inorganic phosphate. The amount of radioactivity incorporated into the enzyme is different depending on the growth phase of the culture, with the highest level ofP incorporation occurring during the mid-exponential growth phase. Previously reported studies have demonstrated that the enzyme is also phosphorylated in vitro in an ATP-dependent reaction. [ABSTRACT FROM AUTHOR]

Prostate-specific antigen (PSA) is regarded as the most sensitive biomarker for prostate cancer. Although androgen/androgen receptor (AR) signaling promotes prostate cancer progression, suppression of AR signaling induces chemokine (CC motif) ligand 2 (CCL2), which enables prostate cancer cells to gain metastatic potential. AR-controlled PSA alone may be an unreliable biomarker for patients receiving androgen deprivation therapy. Therefore, we investigated the validity of CCL2 as a complementary biomarker to PSA for prostate cancer. Our in vitro approach of enriching for prostate cancer cells with higher migration potential showed that CCL2 activated cellular migration. Importantly, we found that CCL2 levels were significantly different between men (n = 379) with and without prostate cancer. Patients with CCL2 ≥ 320 pg/mL had worse overall survival and prostate cancer -specific survival than those with CCL2 < 320 pg/mL. A novel risk classification was developed according to the risk factors CCL2 ≥ 320 pg/mL and PSA ≥ 100 ng/mL, and scores of 2, 1, and 0 were defined as poor, intermediate, and good risk, respectively, and clearly distinguished patient outcomes. CCL2 may serve as a novel biomarker for prostate cancer. The novel risk classification based on combining CCL2 and PSA is more reliable than using either alone.