ISSN:
1572-9699
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract The catabolic metabolism ofHaemophilus parainfluenzae involves the activity of enzymes of the Embden-Meyerhof-Parnas pathway, the hexose monophosphate pathway, and the tricarboxylic acid cycles. The enzymes of these pathways are very likely localized in the cytoplasm of the bacteria and generate the catabolites which have an obligatory reaction with the membrane-bound electron transport system. The catabolites formed interact to reduce or in some cases to reoxidize six distinct primary membrane-bound dehydrogenases of the electron transport system. The obligatory interaction of the catabolic enzyme systems and the membrane-bound electron transport system involves the generation of DPN as beef heart lactic dehydrogenase can substitute for the membrane-bound electron transport system. The utilization of glucose, the reoxidation of reduced pyridine nucleotide, and the growth ofH. parainfluenzae all depend on: 1. a functional electron transport system; and 2. suitable externally supplied electron acceptors. Studies with respiratory inhibitors indicate that the primary dehydrogenases, the quinone, the cytochromes and possibly the cytochrome oxidases are involved. An electron acceptor, either DPN, TPN, fumarate, pyruvate, nitrate or oxygen, must be present. Nitrate and oxygen reoxidize the reduced electron transport system by reoxidizing the cytochrome oxidases. There is preliminary evidence that fumarate, possibly TPN, and pyruvate cause pyridine nucleotide reoxidation by oxidizing the proper primary dehydrogenase.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02097454
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