Biophysics 

About: Biophysics is an academic journal. The journal publishes majorly in the area(s): Membrane & Population. It has an ISSN identifier of 0006-3509. Over the lifetime, 2710 publications have been published receiving 9740 citations. The journal is also known as: Biophysics & biological physics.

Ubiquity of log-normal distributions in intra-cellular reaction dynamics.

Abstract: The discovery of two fundamental laws concerning cellular dynamics with recursive growth is reported. Firstly, the chemical abundances measured over many cells were found to obey a log-normal distribution and secondly, the relationship between the average and standard deviation of the abundances was found to be linear. The ubiquity of these laws was explored both theoretically and experimentally. By means of a model with a catalytic reaction network, the laws were shown to exist near a critical state with efficient self-reproduction. Additionally, by measuring distributions of fluorescent proteins in bacteria cells, the ubiquity of log-normal distribution of protein abundances was confirmed. Relevance of these findings to cellular function and biological plasticity is briefly discussed.

On mechanisms of fluorescence quenching by water

Abstract: Mechanisms of fluorescence quenching of aromatic chromophores by water are reviewed. The mechanisms include polarity of chromophore environment, proton or electron transfer between the excited chromophore and water. A hypothesis is proposed that the quenching can be a result of chromophore-solvent hydrogen bond breaking in the excited state.

Mechanisms of secondary structure breakers in soluble proteins.

Abstract: Breaking signals of secondary structure put strong limitations on the tertiary structures of proteins. In addition to proline and glycine clusters, which are well-known secondary structure breakers, clusters of amphiphilic residues were found to be a novel type of secondary structure breaker. These secondary structure breakers were found to depend on specific environmental factors. Such conditions included the average hydrophobicity, the helical periodicity, the density of serine and threonine residues, and the presence of tryptophan and tyrosine clusters. Principal component analysis of environmental factors was conducted in order to identify candidate breakers in the secondary structure breaking regions. Predicted breakers were located in breaking regions with an accuracy of 72%. Taking the loop core into consideration, almost 90% of the predicted breakers were located in the loop segments. When the migration effect of the breaking point was taken into account, the loop segments with the predicted breakers covered two thirds of all loop segments. Herein, the possibility of secondary structure prediction based on secondary structure breakers is discussed. The system of the present method is available at the URL: http://bp.nuap.nagoya-u. ac.jp/sosui/sosuibreaker/sosuibreaker_submit.html.