Einbau von Thymidin in die DNS von Actinomyceten I. Der Einbau exogenen Thymidins in die DNS von Thermoactinomyces vulgaris

✍ Scribed by Dr. G. Strohbach; Sigrid Kretschmer

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 580 KB
• Volume: 17
• Category: Article
• ISSN: 0233-111X
• DOI: 10.1002/jobm.19770170709

✦ Synopsis

Abstract

The incorporation of exogenous thymidine and thymine into acid‐insoluble material of Thermoactinomyces vulgaris has been studied during germination and subsequent growth

Thymine is not incorporated. The incorporation of thymidine stops after a short time due to the rapid breakdown of thymidine to thymine and deoxyribose‐1‐phosphate by the inducible thymidine phosphorylase

Deoxyadenosine enhances the incorporation of thymidine as well as of thymine and prolongs the time of uptake. Uridine stimulates only the incorporation of thymidine but not of thymine. These effects can be explained by the function of these substances within the salvage pathway. Deoxyadenosine acts as donor of deoxyribosyl groups being necessary for the conversion of thymine to thymidine by thymidine phosphorylase and uridine inhibits thymidine phosphorylase, and thereby it prevents the degradation of thymidine to thymine

Thymidine is incorporated into alkali‐, RNase‐ and protease‐stable, hot TCA‐soluble and DNasesensitive material. That means that the cellular DNA of T. vulgaris can be specifically labelled by radioactive thymidine in the presence of deoxyadenosine and uridine, respectively.