Record Details
Field | Value |
---|---|
Title | The inhibitory effect of cryteine on Streptomyces griseus phage reproduction |
Names |
Nishikawa, Sumie Suzuki
(creator) Gilmour, C. M. (advisor) |
Date Issued | 1965-09-30 (iso8601) |
Note | Graduation date: 1966 |
Abstract | Cysteine inhibition of phage multiplication in Escherichia coli has been described by a number of workers. More recently cysteine has been found to lower the yield of Streptomyces griseus phage. The present study sought a more complete description of the "cysteine effect" as it has been noted in the S. griseus phage-host system. The influence of cysteine was studied by measuring changes in the one-step growth curve of the system or in the relative phage yield. The influence of cysteine concentration, exposure time and site of action were examined. A slight lengthening in the latent period of the S. griseus one-step growth curve and a 75 percent decrease in relative phage yield were observed when 50 μg/ml of cysteine was present through out the entire growth period. A short exposure time of 20 minutes to 50 μg/ml cysteine during the early and middle portion of the latent period also gave maximum inhibition of phage yield. Resuspension of infected cells in fresh medium did not remove the inhibitory effect. This indicated that the ionic balance of the system was not altered. Cysteine did not appear to influence the release of phage particles from the infected host, since the addition of this amino acid during the latter portion of the latent period did not result in a significant decrease in phage yield. In addition, no changes in phage yield were observed when cysteine was present during germination of the host spores or during the period of phage adsorption. A disturbance in the production of an essential amino acid was ruled out since cysteine did not compete with the production of homoserine, methionine, threonine or isoleucine. Other sulfhydryl compounds such as homocysteine, glutathione, and sodium thioglycollate were also found inhibitory to the phage-host system. These findings suggested that the cysteine inhibitory effect was centered at some site in the synthesis of phage protein. |
Genre | Thesis/Dissertation |
Topic | Streptomyces |
Identifier | http://hdl.handle.net/1957/47824 |