the resistance of antimicrobials has become a global hazard with the irrational use of antibiotics. infection of drug-resistance bacteria seriously threatens human health. currently there is an urgent need for the development of novel antimicrobial agents with new mechanisms and lower levels of toxicity. in this paper, a series of (s,z)-4-methyl-2-(4-oxo-5-((5-substitutedphenylfuran-2-yl) methy...

Conflicting reports exist regarding the ability of quinine to activate neurons in the trigeminal system. We used the complementary approaches of single-unit electrophysiology and c-fos immunohistochemistry to investigate whether quinine (100 mM) activates chemonociceptive cells in the brainstem trigeminal subnucleus caudalis (Vc). In electrophysiological experiments, 38 units responded to noxio...

2-Amino-4-chloro-5-(-nitrophenylsulfinyl)pentanoic acid (1) has been synthesized and shown to induce mechanism-based inactivation of two pyridoxal phosphate dependent enzymes: (1 ) cystathionine y-synthetase, which catalyzes a y-replacement reaction in bacterial methionine biosynthesis; and (2) methionine y-lyase, which catalyzes a y-elimination reaction in bacterial methionine breakdown. The i...

The cyclic process of biosynthesis and degradation of poly(3-hydroxyalkanoate) (PHA) was studied in Alcaligenes eutrophus under conditions of nitrogen-limitation of growth. A. eutrophus cells, which had accumulated poly(3-hydroxybutyrate) (PHB) of 55 wt% content within cells from butyric acid, were transferred into a nitrogen-free medium containing pentanoic acid as the sole carbon source and c...

4-Hydroxy-2-keto-pentanoic acid aldolase from Escherichia coli was identified as a class I aldolase. The enzyme was found to be highly selective for the acetaldehyde acceptor but would accept alpha-ketobutyric acid or phenylpyruvic acid in place of the pyruvic acid carbonyl donor.

A new method, involving the use of paper electrophoresis is described for the study of the equilibria in mixed ligand complex systems in solution. This technique is based on the movement ef a spot of metal ion under an electric field with the complexants added in the background electrolyte at p'H = 8.5. Concentration of the primary Iigand (NTA) was kept constant while that of the secondary Iiga...

Three analogues of mevalonic acid have been found to inhibit cholesterol biosynthesis in liver homogenates in the following order of efficacy: 3-methyl-3-hydroxy pentanoic acid > A*3methyl pentenoic acid > As-3-methyl pentenoic acid. The hydroxy acid produces half the maximum inhibition at a concentration of 5 pmoles/ml of homogenate. This corresponds to a ratio of 100 pmoles of inhibitor to 1 ...