There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Evolution of Protein Molecules

The glutathione S-transferases (GST) represent a major group of detoxification enzymes. All eukaryotic species possess multiple cytosolic and membrane-bound GST isoenzymes, each of which displays distinct catalytic as well as noncatalytic binding properties: the cytosolic enzymes are encoded by at least five distantly related gene families (designated class alpha, mu, pi, sigma, and theta GST), whereas the membrane-bound enzymes, microsomal GST and leukotriene C, synthetase, are encoded by single genes and both have arisen separately from the soluble GST. Evidence suggests that the level of expression of GST is a crucial factor in determining the sensitivity of cells to a broad spectrum of toxic chemicals. In this article the biochemical functions of GST are described to show how individual isoenzymes contribute to resistance to carcinogens, antitumor drugs, environmental pollutants, and products of oxidative stress.A description of the mechanisms of transcriptional and posttranscriptional regulat...

The glutathione S-transferase supergene family: regulation of GST and the contribution of the isoenzymes to cancer chemoprotection and drug resistance.

▪ Abstract Insecticide resistance is an increasing problem in many insect vectors of disease Our knowledge of the basic mechanisms underlying resistance to commonly used insecticides is well established Molecular techniques have recently allowed us to start and dissect most of these mechanisms at the DNA level The next major challenge will be to use this molecular understanding of resistance to develop novel strategies with which we can truly manage resistance State-of-the-art information on resistance in insect vectors of disease is reviewed in this context

Insecticide Resistance in Insect Vectors of Human Disease

The molecular basis of insecticide resistance in mosquitoes.

Evidence that DDT-dehydrochlorinase from the house fly is a glutathione S-transferase

Insecticide metabolism by multiple glutathione S-transferases in two strains of the house fly, Musca domestica (L)

Effect of tocotrienols on hepatocarcinogenesis induced by 2-acetylaminofluorene in rats.

A locally isolated Acinetobacter sp. Strain AQ5NOL 1 was encapsulated in gellan gum and its ability to degrade phenol was compared with the free cells. Optimal phenol degradation was achieved at gellan gum concentration of 0.75% (w/v), bead size of 3 mm diameter (estimated surface area of 28.26 mm2) and bead number of 300 per 100 ml medium. At phenol concentration of 100 mg l−1, both free and immobilized bacteria exhibited similar rates of phenol degradation but at higher phenol concentrations, the immobilized bacteria exhibited a higher rate of degradation of phenol. The immobilized cells completely degrade phenol within 108, 216 and 240 h at 1,100, 1,500 and 1,900 mg l−1 phenol, respectively, whereas free cells took 240 h to completely degrade phenol at 1,100 mg l−1. However, the free cells were unable to completely degrade phenol at higher concentrations. Overall, the rates of phenol degradation by both immobilized and free bacteria decreased gradually as the phenol concentration was increased. The immobilized cells showed no loss in phenol degrading activity after being used repeatedly for 45 cycles of 18 h cycle. However, phenol degrading activity of the immobilized bacteria experienced 10 and 38% losses after the 46 and 47th cycles, respectively. The study has shown an increased efficiency of phenol degradation when the cells are encapsulated in gellan gum.

/pdf/enhanced-phenol-degradation-by-immobilized-acinetobacter-sp-iojymtd5zy.pdf

Nor Aripin Shamaan

Papers

Evidence that DDT-dehydrochlorinase from the house fly is a glutathione S-transferase

Insecticide metabolism by multiple glutathione S-transferases in two strains of the house fly, Musca domestica (L)

Effect of tocotrienols on hepatocarcinogenesis induced by 2-acetylaminofluorene in rats.

Enhanced phenol degradation by immobilized Acinetobacter sp. strain AQ5NOL 1.

Characterization of multiple glutathione transferases from the house fly, Musca domestica (L)