Isolation,characterization, and growth of basidiomycetes

Our program on the mass cultivation of basidiomycetes was designed to determine whether these organisms, being more highly differentiated than bacteria, molds, and yeasts, would in turn carry out markedly different reactions on natural products. A discussion of our methods of isolating and characterizing a representative collection of basidiomycetes and of our difficulties in obtaining pure cultures which grew well is presented. Some information we obtained on the growth and types of products that these organisms produced in a synthetic medium is discussed. Our techniques for examining fermentation beers for transformation products from indole compounds and from progesterone are explained, and the types of products we obtained are described.     

Fish scales as Biosensors for Catecholamines

Certain fish scales contain specialized cells (chromatophores) with pigment granulas, which can be dispersed or aggregated in the cells. The degree of aggregation is determined by a transmitter substance, nonadrenaline, released by the sympathetic nerve endings in the skin. Isolated scales from, for example, cuckoo wrasse (Labrus ossifagus) retain a large sensitivity to externally applied nonadrenaline (or more generally catecholamines) for several weeks. The degree of aggregation in isolated scales can be measured objectively by simple photometric techniques. We demonstrate in this paper how fish scales can be used to monitor catecholamine levels in human blood plasma. A discussion of other potential biosensor applications of this intact biological receptor-effector system is also given.     

PHOSPHOLIPID METABOLISM IN SUBACUTE SCLEROSING PANENCEPHALITIS : ACTIVITY OF BRAIN PHOSPHOLIPASE A2 TOWARDS SPECIFICALLY LABELLED 1,2-DIACYL-, 1-ALK-1''-ENYL-2-ACYL- AND 1-ALKYL-2-ACYL-sn-GLYCERO-3-PHOSPHORYLCHOLINE

—1,2-Diacyl-, 1-alk-1′-eny1-2-acyl- and 1-alky1-2-acyl-sn-glycero-3-phosphorylcholine specifically labelled with different fatty acids at the 2 position, were prepared enzymically using the acyltransferase system of rabbit sarcoplasmic reticulum. The substrates were submitted to hydrolysis by phospholipase A₂ (phospholipid acyl-hydrolase, EC 3.1.1.4) obtained from normal and brain tissue affected with subacute sclerosing panencephalitis. In the diseased tissue an increase of phospholipase A₂ activity ranging from 46 to 54% could be observed in comparison to the control brain for all substrates investigated. Among the investigated substrates phospholipase A₂ had the highest affinity for the 1,2-diacylcompound, whereas alkenylacyl- and alkylacyl-sn-glycero-3-phosphorylcholine were cleaved at almost similar rates. The hydrolysis rate of choline-plasmalogen and the corresponding diacyl compound by the enzyme was greatly influenced by the fatty acid moiety located at the 2 position of the substrates.     

Global morphological analysis of marine viruses shows minimal regional variation and dominance of non-tailed viruses

Viruses influence oceanic ecosystems by causing mortality of microorganisms, altering nutrient and organic matter flux via lysis and auxiliary metabolic gene expression and changing the trajectory of microbial evolution through horizontal gene transfer. Limited host range and differing genetic potential of individual virus types mean that investigations into the types of viruses that exist in the ocean and their spatial distribution throughout the world''s oceans are critical to understanding the global impacts of marine viruses. Here we evaluate viral morphological characteristics (morphotype, capsid diameter and tail length) using a quantitative transmission electron microscopy (qTEM) method across six of the world''s oceans and seas sampled through the Tara Oceans Expedition. Extensive experimental validation of the qTEM method shows that neither sample preservation nor preparation significantly alters natural viral morphological characteristics. The global sampling analysis demonstrated that morphological characteristics did not vary consistently with depth (surface versus deep chlorophyll maximum waters) or oceanic region. Instead, temperature, salinity and oxygen concentration, but not chlorophyll a concentration, were more explanatory in evaluating differences in viral assemblage morphological characteristics. Surprisingly, given that the majority of cultivated bacterial viruses are tailed, non-tailed viruses appear to numerically dominate the upper oceans as they comprised 51–92% of the viral particles observed. Together, these results document global marine viral morphological characteristics, show that their minimal variability is more explained by environmental conditions than geography and suggest that non-tailed viruses might represent the most ecologically important targets for future research.     

Cerapeplus gen.n. and the classification of micropeplids (Coleoptera: Micropeplidae)

Cerapeplus siamensis gen.n., sp.n. from Thailand is described and illustrated. The new genus is characterized by filament-based lamellar secretions arising from the lateral body margin, a feature observed for the first time in Coleoptera. Possible autapomorphies for the micropeplid genera are discussed. It is concluded that Cerapeplus and Kalissus are monophyletic; Micropeplus and/Or Peplomicrus are probably polyphyletic but both genera together form a monophyletic group. A number of characters support the family status of the micropeplids recently proposed by some authors. A revised family diagnosis is provided.