Oxygen requirements of Strongyloides papillosus infective larvae

Abstract

1. 1. The free-living, infective larvae of Strongyloides papillosus were found to have a high oxygen consumption. The larvae consumed an average of 28.6 microliters of oxygen per hour per milligram of dry weight ( Q o 2 ). 2. 2. The larvae could not survive in the absence of oxygen. They are therefore classified as “strict aerobes”. 3. 3. The infective larvae were “cyanide sensitive.” Respiration was completely inhibited, resulting in death, by 1 × 10 −3 M HCN. 4. 4. Cytochrome oxidase was detected colorimetrically in larval homogenates. Coupled with the action of HCN, these results indicated the presence of a cytochrome system in the larvae. 5. 5. The comparative results of the Q o 2 of S. papillosus larvae and other parasitic nematode larvae indicated an inverse relationship between Q o 2 and longevity of these forms.