Date of Award

Spring 1982

Degree Type

Thesis - Restricted

Degree Name

Master of Science (MS)



First Advisor

Courtright, James B.

Second Advisor

Kumaran, Krishna A.

Third Advisor

Waring, Gail


The substrate specificities of aldehyde and pyridoxal oxidases have been determined with a variety of aliphatic and aromatic aldehydes. This analysis has lead to the finding that 2,4,5- trimethoxybenzaldehyde is a specific substrate for pyridoxal oxidase (P0) and that heptaldehyde is oxidized preferentially by aldehyde oxidase (AO). The tissue specific localization of AO and PO in the wild type larval and adult structures has been determined both by selective staining of wild type tissues with either heptaldehyde or 2,4,5-trimethoxybenzaldehyde and by comparing the aldoxn and lpo tissue specific enzyme pattern obtained with benzaldehyde. By using these procedures, AO was identified in all the major internal organs of the wild type larva and adult, including brain, imaginal discs, malpighian tubules, digestive system and reproductive structures. In these wild type strains pyridoxal oxidase is present in many of the same structures which possess AO, but is missing from the cardia, crop , imaginal discs, ovarian follicle cells, paragonia, pericardial cells, hindgut and wreath cells. The distribution of AO in cin2 mutant larva and adults raised at 22°C was limited to those tissues that normally express only AO and not PO activity in wild type. At this temperature no PO activity was found in any cin2 larva or adult tissues. These histochemical patterns of AO and PO distribution were also confirmed by enzymatic analysis of the activities present in homogenates of various individual tissues. There is a temperature sensitivity associated with the cin2 mutation and consequently AO, PO and XDH activities are not present in extracts from individuals raised at 28°C. However, the electrophoretic and physical properties of the AO in individuals raised at permissive temperatures was indistinguishable from wild type. Thus, an active cin2 factor does not appear to be a structural component of AO but is required for AO expression in the developing tissues.