Monstrous People > Mutants, clones and cyborgs

Science news on Tech, Genetics, and all variations.

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onishadowolf:
I found articles on that too. They are doing social experiments, and finding genes and RNA coders that cause certain social behavior. Just got to tired to post them.

And the last article about the manipulated  virus cancer killers; vaguely reminds me of the movie "I am legend".     :crazy:

Moloch:
That's also vaguely similar to the whole "T" cell stuff they used for an explanation in Resident Evil.

onishadowolf:
You mean the T virus. The virus in Resident Evil series that reanimates dead cells. Yeah it does.

onishadowolf:
ScienceDaily (June 9, 2009) — A synthetic DNA binding compound has proved surprisingly effective at binding to the DNA of bacteria and killing all the bacteria it touched within two minutes. The DNA binding properties of the compound were first discovered in the Department of Chemistry at the University of Warwick by Professor Mike Hannon and Professor Alison Rodger (Professor Mike Hannon is now at the University of Birmingham). However the strength of its antibiotic powers have now made it a compound of high interest for University of Warwick researchers working on the development of novel antibiotics.

Dr Adair Richards from the University of Warwick said: "This research will assist the design of new compounds that can attack bacteria in a highly effective way which gets around the methods bacteria have developed to resist our current antibacterial drugs. As this antibiotic compound operates by targeting DNA, it should avoid all current resistance mechanisms of multi-resistant bacteria such as MRSA."
The compound [Fe2L3]4+ is an iron triple helicate with three organic strands wrapped around two iron centres to give a helix which looks cylindrical in shape and neatly fits within the major groove of a DNA helix. It is about the same size as the parts of a protein that recognise and bind with particular sequences of DNA. The high positive charge of the compound enhances its ability to bind to DNA which is negatively charged.
When the iron-helicate binds to the major groove of DNA it coils the DNA so that it is no longer available to bind to anything else and is not able to drive biological or chemical processes. Initially the researchers focused on the application of this useful property for targeting the DNA of cancer cells as it could bind to, coil up and shut down the cancer cell's DNA either killing the cell or stopping it replicate. However the team quickly realised that it might also be a very clever way of targeting drug-resistant bacteria.
New research at the University of Warwick, led by Dr Adair Richards and Dr Albert Bolhuis, has now found that the [Fe2L3]4+ does indeed have a powerful effect on bacteria. When introduced to two test bacteria Bacillus subtilis and E. coli they found that it quickly bound to the bacteria's DNA and killed virtually every cell within two minutes of being introduced - though the concentration required for this is high.
Professor Alison Rodger, Professor of Biophysical Chemistry at the University of Warwick, said: "We were surprised at how quickly this compound killed bacteria and these results make this compound a key lead compound for researchers working on the development of novel antibiotics to target drug resistant bacteria."
The researchers will next try and understand how and why the compound can cross the bacteria cell wall and membranes. They plan to test a wide range of compounds to look for relatives of the iron helicate that have the same mechanism for action in collaboration with researchers around the world.
Journal reference:
Richards et al. Antimicrobial activity of an iron triple helicate. International Journal of Antimicrobial Agents, 2009; 33 (5): 469 DOI: 10.1016/j.ijantimicag.2008.10.031

onishadowolf:
ScienceDaily (Nov. 6, 2008) — When a dividing cell duplicates its genetic material, a molecular machine called a sliding clamp travels along the DNA double helix, tethering the proteins that perform the replication. Researchers from the laboratory of Rockefeller University’s Michael O'Donnell, a Howard Hughes Medical Institute investigator, have discovered a small molecule that stops the sliding clamp in its tracks.

The finding will enable scientists to better study the proteins that duplicate DNA, and may ultimately provide a platform for developing improved antibiotics.
The process is akin to unzipping a zipper: The sliding clamp works its way along the DNA double helix while a network of proteins work together to unwind the two strands. Proteins known as polymerases then add, in assembly-line fashion, nucleotide bases — the building blocks that make up DNA — to convert the now-single-stranded templates into two new duplex DNA molecules. Bacteria have five known DNA
polymerases (higher organisms such as humans have more), only one of which, polymerase III (pol III) is responsible for replicating the chromosome, while the others appear to be involved in DNA repair.
To better understand the functions of the other polymerases, O’Donnell and colleagues at Rockefeller used a combination of biochemical techniques to identify a small molecule that would inhibit the binding of the polymerases to the beta sliding clamp. With the help of researchers in Rockefeller’s High Throughput Screening Resource Center, coauthors Roxana E. Georgescu and Olga Yurieva, research associates in O’Donnell’s lab, screened some 30,000 compounds using a technique called fluorescence anisotropy. Georgescu and Yurieva looked for compounds that would disrupt the interaction of a fluorophore-labeled peptide with the peptide-binding pocket of the sliding clamp. Because the peptide is small and the clamp is big, the signal generated by the fluorophore is very different.
Georgescu and Yurieva identified one compound, called RU7, that differentially inhibited polymerases II, III and IV. RU7 did not inhibit pol IV at all, while pol III was inhibited the most.
The researchers then used x-ray crystallography to compare how RU7 and polymerases II, III and IV bind to the clamp. They found that while all three polymerases and RU7 bind to the same peptide-binding site of the clamp, they do so in different ways. Polymerase IV, for example, forms additional contacts to the clamp outside of the peptide-binding site, which may account for its resistance to disruption by RU7.
“The role of polymerase III in replication has been very well studied, but the roles of the other polymerases are not well understood,” says O’Donnell. “RU7 may be an important tool as a chemical probe to better understand the functions of polymerases II and IV in normal cell growth and in response to DNA damage.”
Because RU7 halts the replication of bacterial DNA by disrupting polymerase III — but does not affect DNA replication in yeast, which uses the same molecular machinery as humans — O’Donnell’s research suggests that RU7 could provide a starting point for antibiotic drug design. Further tweaking, for example by adding atoms that enable the compound to fit into a second binding site, could even increase RU7’s potency.
Journal reference:
Georgescu et al. Structure of a small-molecule inhibitor of a DNA polymerase sliding clamp. Proceedings of the National Academy of Sciences, 2008; 105 (32): 11116 DOI: 10.1073/pnas.0804754105

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