Surface absorption of aluminium by gill tissue and body mucus of rainbow trout, Salmo gairdneri, at the onset of episodic exposure

Rainbow trout were exposed to an episode of artificial soft water at pH 5.4 containing 0.95 mg 1 -1 of aluminium for 1 h and gill, skin, body mucus and blood aluminium concentrations were determined. Skin and blood showed no significant increase in aluminium content, whereas whole gill tissue and body mucus showed significant increases. The results are discussed in terms of the gill and body mucus being major sites of aluminium absorption, and a tentative mechanism for aluminium absorption is discussed.     

Evolutionary anomalies among the aminoacyl-tRNA synthetases

Unexpected relationships among the various aminoacyl-tRNA synthetases continue to be uncovered. The question arises — is this mainly the result of promiscuous exchange, or is the confusion really a reflection of the differential loss of past duplications? Phylogenetic analysis may yet provide the answer.