Novel Aspects Of The Transport Of Organic Anions By The Malpighian Tubules Of Drosophila Melanogaster

Para-aminohippuric acid (PAH) is a negatively charged organic ion that can pass across the epithelium of Malpighian tubules. Its mode of transport was studied in Malpighian tubules of Drosophila melanogaster. PAH transport was an active process, with a K(m) of 2. 74 mmol l(-)(1) and a V(max) of 88.8 pmol min(-)(1). Tubules had a low passive permeability to PAH, but PAH transport rates (832 nmol min(-)(1 )mm(2)) and concentrative ability …