Document Detail

Hyperbaric oxygen toxicity and ribosome destruction in Escherichia coli K12.
MedLine Citation:
PMID:  6163514     Owner:  NLM     Status:  MEDLINE    
The viability of resting suspensions of Escherichia coli K12 Ymel exposed to air plus 300 psi (1 psi = 6.895 kPa) oxygen (hyperbaric oxygen) decreased as an apparent first-order process after an initial period of constant viability. Control suspensions exposed to air plus 300 psi nitrogen (hyperbaric nitrogen) did not lose viability over the 96 h of the experiment. It was observed that a decrease in the refractive index of the cells preceded the loss of viability in hyperbaric oxygen. This finding together with electron micrographs, which showed extensive loss of ribosomal particles in bacteria incubated in hyperbaric oxygen, led us to suspect that ribosome injury or disassociation might be important in hyperbaric oxygen toxicity. In support of this we found that cellular RNA, labeled with [5-3H]uridine, was much more rapidly and more completely degraded in hyperbaric oxygen than in hyperbaric nitrogen. Furthermore, a far greater proportion of RNA was degraded than was DNA or protein. A direct assay for ribosome particles by sucrose gradient centrifugation showed that only 34% of the 70S ribosome particles was lost during the first 24 h in hyperbaric nitrogen whereas in hyperbaric oxygen 99.6% of the 70S particles was degraded during the same period. In hyperbaric oxygen the rate of viability loss between 24 and 72 h was equal to the rate of 70S ribosome degradation during the first 24 h. If 70S ribosome disassociation in hyperbaric oxygen continues at the same rate after first 24 h, then cumulative 70S ribosome disassociation or injury may lead to and provide an explanation for irreversible bacterial cell injury and the loss of viability.
J B Harley; J G Flaks; H Goldfine; M E Bayer; H Rasmussen
Related Documents :
17604574 - Genetic diversity of coastal bottlenose dolphins revealed by structurally and functiona...
9686164 - Influence of body mass and environmental oxygen tension on the oxygen consumption rates...
12373084 - Functional studies on nine different haemoglobins with high oxygen affinity.
12181134 - Oxygen transport across vasa recta in the renal medulla.
11321604 - Effects of an aerobic rowing training regimen in young adults with down syndrome.
17253114 - A pilot study to assess the feasibility of a submaximal exercise test to measure indivi...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Canadian journal of microbiology     Volume:  27     ISSN:  0008-4166     ISO Abbreviation:  Can. J. Microbiol.     Publication Date:  1981 Jan 
Date Detail:
Created Date:  1981-06-25     Completed Date:  1981-06-25     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0372707     Medline TA:  Can J Microbiol     Country:  CANADA    
Other Details:
Languages:  eng     Pagination:  44-51     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Atmospheric Pressure
Bacterial Proteins / metabolism
Culture Media
DNA, Bacterial / metabolism
Escherichia coli / drug effects*,  metabolism,  ultrastructure
Glucose / metabolism
Nitrogen / pharmacology
Oxygen / pharmacology*
RNA, Bacterial / metabolism
Ribosomes / drug effects*,  metabolism
Grant Support
Reg. No./Substance:
0/Bacterial Proteins; 0/Culture Media; 0/DNA, Bacterial; 0/RNA, Bacterial; 50-99-7/Glucose; 7727-37-9/Nitrogen; 7782-44-7/Oxygen

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Importance of monovalent ions for the fast axonal transport of proteins.
Next Document:  Determination of the total rates of synthesis and degradation of RNA in a bacterial culture.