Organic chemists discover a new method to selectively make cis carbon-fluorine bonds
The primary concern of organic chemists is to make molecules of socio-economic benefit, such as polymers, medicines and agrochemicals. To this end, many organic chemists interest themselves in being able to discover new ways of making chemical bonds to help them build these molecules.
The carbon-fluorine bond is one of unique interest among chemists, this bond is especially strong due to it combining factors of covalent (electron-sharing) and ionic (attraction between opposite charges) character into the union of the two atoms. Having access to these bonds allow chemists to build pharmaceutical compounds with extra strength and stability in their carbon framework and stronger, more durable polymers.
Mario P. Weisenfeldt and his team have discovered a new synthetic method that adds hydrogen atoms to the same face of cyclic molecules made up of carbon and fluorine bonds, which pushes all of the carbon-fluorine bonds to one side or face of the cyclic structure.
This cis-fluorinated compound exhibits interesting electronic properties which could have applications in materials science. In any case, Weisenfeldt and his team’s discovery has opened up a new method of synthesis that will make life easier for chemists to make vital compounds needed for everyday life.
The threat of deportation in America and how it impacts the development of children
The fate of immigrants in America has been the subject of widespread media coverage and debate in recent months, with the current US administration rescinding the DACA policy. In a social experiment designed by Jens Hainmueller and researchers at Stanford University, the impact of the risk of deportation of mothers on their children’s mental health was investigated.
The study found that mothers who had birth dates just before the cutoff of the DACA policy and thus protected from deportation, had children with 50% fewer diagnoses of anxiety and stress-related disorders.
On the other hand, mothers who were not protected from deportation under DACA had children who were more likely to suffer from these anxiety and adjustment disorders. The results of this study underpin the negative impact that aggressive deportation policies can have on the development and future opportunities of children affected by such policies.
Crispr biology: the path to better understanding this amazing new technology
The discovery of the CRISPR-Cas gene in bacteria, has precipitated a furious maelstrom of scientific discovery and innovation in recent years. Originally used as a defence mechanism by bacteria against viruses, this DNA detecting and editing machine within bacteria allows them to snip off pieces of DNA from attacking viruses and integrate it within their own DNA sequence to allow them to detect and prevent future attacks from similar viruses.
Scientists have been able to re-engineer the bacterial proteins that carry out this process and re-direct them towards gene-editing so that we can permanently modify genes within organisms with the potential to make more efficient crops and fermenting bacteria for producing food and beverages, as well as treating diseases.
Researchers from the University of California Berkeley have recently conducted experiments to better elucidate the mechanism by which the bacterial CRISPR proteins execute this gene detection and editing process.
By employing crystal structure analysis and cryo-electron microscopy, the researchers have discovered that the ‘snipping’ process is carried out by a bacterial protein called Integration Host Factor (IHF) that binds to the viral DNA and bends it sharply so that it comes into contact with another CRISPR protein called Cas-1.
This process is thought to increase the specificity and efficiency of the integration process, and expanding our understanding of how the integration process works will allow scientists to better utilize this incredibly versatile technology along multiple lines, generating exciting prospects for future breakthroughs with CRISPR.
The marriage of anthropology and genetics – tracing the pattern of human migration in Papua New Guinea
Analysing and cross referencing the genetic codes of different peoples throughout the continents has allowed scientists to piece together the patterns of human migration over hundreds of thousands of years.
By comparing similar genetic sequences in peoples of different regions, scientists can ascertain whether there was a migration of a group from one region and subsequent settling in another. The genetic similarities among peoples in two regions can be seen as a sort of fingerprint of that group’s origin in another region prior to migration.
The first comprehensive genetic analysis of the peoples of Papua New Guinea was recently undertaken by scientists at the Wellcome Trust Sanger Institute, University of Oxford and Papua New Guinea Institute of Medical Research.
Their results reveal striking differences between the genetic codes of people in Papua New Guinea and peoples in Europe and Asia, indicating that the groups have remained genetically independent for at least 50,000 years with Papua New Guinea developing independently of Europe and Asia over that period. And that the peoples inhabiting the more isolated highland regions of Papua New Guinea have remained completely genetically independent.
What struck the researchers in particular was the surprising degree of genetic diversity among different groups living within Papua New Guinea that coincides with the vast diversity of language and culture among people in the region.
The results suggest that there was a lack of mixing among peoples of different genetic character in Papua New Guinea as opposed to the considerable mixing that occurred in Europe and Asia.
The researchers have proposed that historical processes such as the Iron and Bronze age that occurred in Europe and Asia but not in Papua New Guinea may have been responsible for the considerable genetic mixing in Europe and Asia, and that the genetic diversity of Papua New Guinea could give scientists insight into the genetic structure, cultural and linguistic diversity of the people of Europe and Asia prior to the Bronze and Iron Ages.