Versatile catechol dioxygenases in <Emphasis Type="Italic">Sphingobium scionense</Emphasis> WP01<Superscript>T</Superscript>

The objective was to understand the roles of multiple catechol dioxygenases in the type strain Sphingobium scionense WP01^T (Liang and Lloyd-Jones in Int J Syst Evol Microbiol 60:413–416, 2010a) that was isolated from severely contaminated sawmill soil. The dioxygenases were identified by sequencing, examined by determining the substrate specificities of the recombinant enzymes, and by quantifying gene expression following exposure to model priority pollutants. Catechol dioxygenase genes encoding an extradiol xylE and two intradiol dioxygenases catA and clcA that are highly similar to sequences described in other sphingomonads are described in S. scionense WP01^T. The distinct substrate specificities determined for the recombinant enzymes confirm the annotated gene functions and suggest different catabolic roles for each enzyme. The role of the three enzymes was evaluated by analysis of enzyme activity in crude cell extracts from cells grown on meta-toluate, benzoate, biphenyl, naphthalene and phenanthrene which revealed the co-induction of each enzyme by different substrates. This was corroborated by quantifying gene expression when cells were induced by biphenyl, naphthalene and pentachlorophenol. It is concluded that the ClcA and XylE enzymes are recruited in pathways that are involved in the degradation of chlorinated aromatic compounds such as pentachlorophenol, the XylE and ClcA enzymes will also play a role in degradation pathways that produce alkylcatechols, while the three enzymes ClcA, XylE and CatA will be simultaneously involved in pathways that generate catechol as a degradation pathway intermediate.     

The biology and chemistry of antifungal agents: A review

In recent years their has been an increased use of antifungal agents and has resulted in the development of resistance to drugs. Currently, use of standard antifungal therapies can be limited because of toxicity, low efficacy rates. Different types of mechanisms contribute to the development of resistance to antifungals. This has given raise to search for a new heterocycle with distinct action or multitargeted combination therapy. This review addresses the areas such as the underlying mechanisms, eight different targets such as ergosterol synthesis, chitin synthesis, ergosterol disruptors, glucan synthesis, squalene epoxidase, nucleic acid synthesis, protein synthesis, microtubules synthesis. The clinically employed drugs along with the current research work going on worldwide on different heterocycles are discussed. In recent advances various heterocycles including imidazole, benzimidazole etc., twenty three scaffolds and their lead identification are discussed.     

Adenosine triphosphatase of Aspergillus nidulans: existence of isoenzymes of Ca2+-ATPase.

Ca2+-ATPase activity increased five- to six fold when the cells were subjected to growth at 37 degrees C in protein hydrolysate-supplemented media as compared to that of the cells grown in minimal media. One major isoenzyme and one minor isoenzyme were present in minimal-medium-grown cells while two major isoenzymes were present in the cells grown in protein-supplemented media. When the cells were subjected to heat stress (43 degrees C), they exhibited significantly decreased activity as compared to 37 degrees C grown cells. However, all the cultures subjected to growth at 43 degrees C showed two isoenzymes independent of growth medium.