The genetic relationship between the human foetal acetylesterase ESA7 and the adult acetylesterase ESA5.
(1) There are very few clear examples among human enzymes of foetal isozymes which are the products of foetal specific gene loci. Earlier studies had pointed to the foetal brain esterase ESA7 as a probable example. (2) Detailed biochemical investigation of partially purified human adult brain ESA5 and the foetal esterase ESA7 has revealed a close resemblance in the biochemical properties of these two isozymes. In addition to similarities in substrate specificity and inhibition sensitivity the two esterases have the same molecular size (c. 57,000), are both relatively unstable at 37 degrees C and show decreased anodal electrophoretic mobility after storage at 20 degrees C. Furthermore there was suggestive evidence that ESA7 and ESA5 may be interconvertible. (3) A variant esterase isozyme pattern, which shows unusual features of both ESA7 and ESA5, was found in a survey of 120 foetal brains. This variant pattern is consistent with a monomeric structure for both esterases and points strongly to a common genetic determination.
D000115:Acetylesterase / Q000235:genetics* / Q000302:isolation & purification; D000328:Adult; D001921:Brain / Q000201:enzymology*; D002852:Chromatography, Ion Exchange; D004355:Drug Stability; D004591:Electrophoresis, Polyacrylamide Gel; D004592:Electrophoresis, Starch Gel; D014644:Genetic Variation; D006358:Hot Temperature; D006801:Humans; D007527:Isoenzymes / Q000235:genetics* / Q000302:isolation & purification
D007527:Isoenzymes; D000115:Acetylesterase