On a One-Dimensional Diffusion Method of Assaying Antibiotic Substances and Its Fundamental Formulas

Biometrics ◽  
1949 ◽  
Vol 5 (4) ◽  
pp. 317 ◽  
Author(s):  
Motosaburo Masuyama
Keyword(s):  
Diffusion Method ◽  
One Dimensional ◽  
Dimensional Diffusion

scholarly journals A One-dimensional Diffusion Method of Assaying Streptomycin

1949 ◽  
Vol 51 (1-2) ◽  
pp. 56-56
Author(s):  
Nakao Ishida ◽  
Ken Katagiri ◽  
Reiko Chida ◽  
Toyo Hataya
Keyword(s):  
Diffusion Method ◽  
One Dimensional ◽  
Dimensional Diffusion

A Method for the Measurement of Fibrinolytic Activity Based on One Dimensional Diffusion Using Small Glass Tubes

1977 ◽  
Vol 37 (03) ◽  
pp. 456-463 ◽  
Author(s):  
Taro Yasukouchi ◽  
Masaru Fujine ◽  
Sukehiro Kohn ◽  
Shoki Sakurama ◽  
Tokiyo Morioka ◽  
...  
Keyword(s):  
Fibrinolytic Activity ◽  
Final Concentration ◽  
Diffusion Method ◽  
Essential Difference ◽  
Optimal Conditions ◽  
One Dimensional ◽  
Dimensional Diffusion ◽  
Small Glass ◽  
Glass Tubes ◽  
The One

SummaryThe optimal conditions for the measurement of the fibrinolytic factors of plasma were examined using human and bovine plasminogen-rich fibrinogen or plasminogen-free fibrinogen as the substrates using the one dimensional diffusion method.The results were as follows:1. There was no essential difference found between using human or bovine fibrinogen.2. The levels of proactivator-plasminogen and plasminogen could be measured while using either plasminogen-rich or plasminogen-free fibrinogen. But, in using the latter, the proactivator-plasminogen level could not be measured, if a final concentration of more than 2,000 Christensen units of streptokinase were employed.3. When using plasminogen-rich fibrinogen, anti-plasmin(s) and anti-activator(s) could be measured while using urokinase and plasmin, but not while using streptokinase. However, further study should be given to the measurement of the inhibitors, when using plasminogen-free fibrinogen.

scholarly journals Hopping and Flipping of RNA Polymerase on DNA during Recycling for Reinitiation after Intrinsic Termination in Bacterial Transcription

2021 ◽  
Vol 22 (5) ◽  
pp. 2398
Author(s):  
Wooyoung Kang ◽  
Seungha Hwang ◽  
Jin Young Kang ◽  
Changwon Kang ◽  
Sungchul Hohng
Keyword(s):  
Single Molecule ◽  
Transcription Initiation ◽  
Molecular Mechanisms ◽  
Facilitated Diffusion ◽  
One Dimensional ◽  
Bacterial Transcription ◽  
Fluorescence Measurements ◽  
Dimensional Diffusion ◽  
Single Molecule Studies ◽  
Hopping Diffusion

Two different molecular mechanisms, sliding and hopping, are employed by DNA-binding proteins for their one-dimensional facilitated diffusion on nonspecific DNA regions until reaching their specific target sequences. While it has been controversial whether RNA polymerases (RNAPs) use one-dimensional diffusion in targeting their promoters for transcription initiation, two recent single-molecule studies discovered that post-terminational RNAPs use one-dimensional diffusion for their reinitiation on the same DNA molecules. Escherichia coli RNAP, after synthesizing and releasing product RNA at intrinsic termination, mostly remains bound on DNA and diffuses in both forward and backward directions for recycling, which facilitates reinitiation on nearby promoters. However, it has remained unsolved which mechanism of one-dimensional diffusion is employed by recycling RNAP between termination and reinitiation. Single-molecule fluorescence measurements in this study reveal that post-terminational RNAPs undergo hopping diffusion during recycling on DNA, as their one-dimensional diffusion coefficients increase with rising salt concentrations. We additionally find that reinitiation can occur on promoters positioned in sense and antisense orientations with comparable efficiencies, so reinitiation efficiency depends primarily on distance rather than direction of recycling diffusion. This additional finding confirms that orientation change or flipping of RNAP with respect to DNA efficiently occurs as expected from hopping diffusion.

Sign in / Sign up

Export Citation Format

Share Document