Second cytotoxic pathway of diphtheria toxin suggested by nuclease activity
Article Abstract:
Diphtheria is a serious, highly contagious disease. Caused by bacteria, it is spread by contact with an infected person or via food. Breathing and swallowing become difficult as the bacteria multiply in the throat, and a breathing tube may need to be inserted surgically. Toxins produced by the diphtheria bacteria enter the blood and can damage the heart and nervous system; death may follow quickly if antitoxin and penicillin are not given promptly. In most developed countries the disease is now rare, thanks to immunization programs. The way in which diphtheria toxin (DTx) attacks and damages cells is not yet fully understood. The experiment described suggests that DTx unravels and inactivates cell DNA (deoxyribonucleic acid, the genetic code) before rupturing the cell. It appears that body cells do not break open simply because protein synthesis slows down, but a second destructive action is taken by DTx; this pathway involves an enzyme called a nuclease.
Publication Name: Science
Subject: Science and technology
ISSN: 0036-8075
Year: 1989
User Contributions:
Comment about this article or add new information about this topic:
Teetering on the brink of danger
Article Abstract:
Three research teams disproved the notion of a neonatal education period for the self-unself immune-system model postulated by Nobel winners F.M. Burnet and P.B. Medawar. One team leader, Polly Matzinger, proposes a new model, in which the immune system responds to antigens associated with danger.
Publication Name: Science
Subject: Science and technology
ISSN: 0036-8075
Year: 1996
User Contributions:
Comment about this article or add new information about this topic:
New Alzheimer's therapy suggested
Article Abstract:
New studies support a controversial inflammatory-disease theory of Alzheimer's dementia. Joe Rogers found that the anti-inflammatory indomethacin slowed the advance of Alzheimer's, and Patrick McGeer found low incidence of Alzheimer's among patients treated for rheumatoid arthritis.
Publication Name: Science
Subject: Science and technology
ISSN: 0036-8075
Year: 1993
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Recognition of a peptide antigen by heat shock-reactive gamma delta T lymphocytes. Detection of a human intracisternal A-type retroviral particle antigenically related to HIV
- Abstracts: Recognition of a peptide antigen by heat shock-reactive gamma delta T lymphocytes. part 2 T cell receptor-MHC Class I peptide interactions: affinity, kinetics, and specificity
- Abstracts: Removal of contaminants from saturated clay by electroosmosis. Contaminants in used lubricating oils and their fate during distillation hydrotreatment re-refining
- Abstracts: Soft-ground subway construction. Vacuum excavation makes clean sweep of utilities. Trench boxes help get to the bottom of this
- Abstracts: Science and diversity: a compelling national interest. Postmodernism. President's lecture: the need for scientific communication with the public