Nobel Prizes and the Immune System

Nobel Prizes are given NOT to Technology but to

studies that contribute to basic understanding of various areas in science,

to innovative ideas that has led us to a paradigm shift in realizing the truth,

ultimately benefiting the human race.

Here is a wonderful link that enlists the milestone discoveries in Immunology that won Nobel Prize over the years, from 1901 to 1996!

http://www.nobelprize.org/nobel_prizes/medicine/immune_responses.html

- DR. P. Kumarasamy

 

VACCINES FOR PARKINSON'S DISEASE!

Vaccines are developed even for diseases that are not caused by pathogens. Parkinson's Disease (PD) is one such.

 How Parkinson's Disease is caused?

Proteins in our body have a specific three dimensional structure. Soon after protein synthesis, they automatically fold into their own predetermined 3D structures through specific folding patterns. Any misfolding of proteins will result in a defective 3D structure that leads to malfunctioning of that protein.

In brain cells, one of the proteins called α-synuclein is essential for the normal brain function. In Parkinson’s disease, there is an accumulation of misfolded α-synuclein proteins called Lewy bodies. This misfolded protein clumps throughout the brain as Parkinson’s disease progresses. Brain cells fail to process and clear these proteins. This leads to the destruction of certain (dopaminergic) neurons, a condition called Lewy neuritis. This leads to the manifestation of the Parkinson’s Disease.

 The PD Vaccine under trial now!

Parkinson’s vaccine is simply the administration of the misfolded alpha-synuclein as antigens which will stimulate our immune system to respond against alpha-synuclein by forming antibodies against these misfolded proteins. These anti-misfolded α-synuclein antibodies will bind to these brain proteins and ultimately clear them.

Proteins sweeter than sugars!

Monellin, incidentally is the first sweet protein to be identified and was discovered in 1969 in the fruit of the West African shrub known as serendipity berry (Dioscoreophyllum cumminsii) and was first mistook to be a carbohydrate!

The protein was named in 1972 after the Monell Chemical Senses Center in Philadelphia, U.S.A., where it was isolated and characterized.
For humans, monellin is 100,000 times sweeter than sucrose.
There are four more such high intensity sweet proteins identified so far

• Thaumatin (1972),
• Pentadin (1989),
• Mabinlin (1983) and
• Brazzein (1994).

- Dr. P. Kumarasamy

Dedicated to Bats of the World

This year (and 2011 too) has been declared as the International Year of Bats.

Bats are the poorly understood of all mammals.

There are many myths surrounding bats, often they describe bats as blood sucking, evil dragons of the night.

It terms of the number of species bats is the second largest among mammals next to rodents.

Here I bring you a photo-montage on bats that I made.

Hope you all enjoy this.

http://youtu.be/BD8UnehL-D8

- Dr. P. Kumarasamy

Transformer Proteins!

Few proteins can transform their domain structure from one secondary structural form to another, say for example from alpha to beta upon a suitable stimulus. What is interesting is that the same protein that has transformed into two distinct structures accomplish entirely two different functions in bacteria – a protein pleiotropism!?

Gene expression starts with Transcription. The transcription process is a cyclic event consisting of three major steps: initiation, elongation, and termination. The enzyme RNA polymerase (RNAP), is responsible for the starting step in gene expression, the mRNA synthesis.

Recent studies show the fact that RNA polymerase, the enzyme that transcribes DNA into RNA, is a target for numerous regulatory events in all living cells.

The RfaH protein is a bacterial elongation factor, involved in Transcription. During transcription, RfaH remains bound to the enzyme, RNA polymerase (RNAP) and acts as an antiterminator by reducing two important processes,  pausing and termination.  Irina Artsimovitch of Ohio State University solved the structure of RfaH Protein in 2007.

Irina Artsimovitch along with Paul Rösch and Artsimovitch’s team at the University of Bayreuth made an interesting discovery recently.

Their studies in the most common micro flora of the gut, Escherichia coli, lead to the discovery that RfaH protein is made-up of two distinct domains connected by a flexible linker - a C-terminal half of the RfaH protein that resembles nunchucks (apha-hairpin-alpha) and an amino-terminal domain (N-Terminal Domain, NTD) that recognizes and binds to the RNA polymerase which is essential for the transcription process.

The two domains are closely associated initially. During transcription initiation, the binding of the NTD of RfaH to DNA leads to a spatial separation of the two domains (CTD and NTD). This acts as a signal for a structural switch CTD of the RfaH protein. The structural switch results in a complete structural rearrangement of the CTD structure from the alpha helical hairpin into a fold that completely different beta barrel structure.

Now, the β-barrel domain recruits ribosome and help in the translation process of the transcribed product.

This transforming ability in the structure allows this RfaH protein to physically couple the processes of transcription and translation in gene expression.

The change in the structure of the RfaH protein happens to turn on those genes that give E. coli its ability to infect.

-         Dr. P. Kumarasamy

Meet the Relatives

The First Australopithecus, 1925

The discovery of the 2.5-million-year-old Taung Child skull marked a turning point in the study of human brain evolution.

Australian anatomy professor Raymond Dart was adjusting the collar of his dress suit in preparation for a friend’s wedding when a box, shipped from a limestone quarry near Taung, South Africa, arrived at the doorstep of his Johannesburg home in November 1924. Dart abandoned his collar to dig through the package’s contents—all the while ignoring the grumblings of  his wife and the groom, who were anxious to begin the wedding ceremony. Inside the box, he found a fossilized mold of a brain and a matching child’s skull partially buried in stone. Dart quickly realized the significance of the finding, and by February 1925 had published an article in Nature identifying a new species: Australopithecus africanus. The 2.5-million-year-old “Taung Child” or “Taung Baby,” as Dart called it, was the first member of theAustralopithecus genus discovered, and it challenged contemporary ideas about human evolution.

According to the era’s prevailing view— “proven” by the anatomy of the Piltdown specimen, which was later unmasked as a hoax—increases in brain size preceded the emergence of other human attributes during early hominin evolution. While the Taung skull had human-like characteristics such as small canines, a steep forehead, and a spinal cord alignment that suggested bipedalism, Taung’s brain size was closer to that of a nonhuman ape. The fossil “heralded a new direction” in the study of human evolution, says Kieran McNulty, a paleoanthropologist at the University of Minnesota, by providing evidence that changes in brain size lagged behind the development of a human-looking face and upright walking. Nevertheless, the fossilized endocranial cast, or endocast, suggested to Dart that Taung’s brain was beginning to reorganize in recognizably human ways. Dart calculated that the ratio of cerebral cortex to cerebellum in Taung’s brain was larger than in gorillas and chimpanzees and also noticed that a groove on the outside of the brain, the lunate sulcus, appeared to have moved backward into a position closer to that seen in humans.

Although Dart’s discovery instantly made him famous, many anthropologists met his interpretations with extreme skepticism. The study of human evolution was still in an “embryonic stage,” says Goran trkalj, a biological anthropologist at Australia’s Macquarie University. Taung’s small brain flouted orthodox theories, leading some anthropologists to group the extinct species with gorillas and chimpanzees. It wasn’t until 1932 that A. africanus was classified as a hominin, and not until the 1940s, as more Australopithecusfossils were identified, that the field began to accept Taung.

Scientists are still learning from the Taung skull and endocast. In humans, a seam along the frontal bone closes slowly because the brain expands rapidly after birth. But in nonhuman apes, it fuses and ossifies quickly. Taung, now estimated to be about 3 or 4 years old at the time of death, retains this “persistent metopic suture,” suggesting its brain development had already diverged from that of the other apes, says Dean Falk, who studies the evolution of cognition at Florida State University. But many unanswered questions of developmental timing and patterns remain, says McNulty. “We’ll be looking at Taung for decades to come.”

- by Sabrina Richards | July 1, 2012 issue of The Scientist

----------------------------------------------------------------------------------------------------------------------------

Meet some of the most famous fossil discoveries of the hominin clan in this slide show.

http://the-scientist.com/2012/07/01/meet-the-relatives/

A NOVEL ANTIMICROBIAL PEPTIDE FROM SCORPIONS

Zeng and associates from the Department of Biotechnology, Wuhan University,  China initially reported (in 2004) type presence of  four novel peptides (BmKa1, BmKa2, BmKb1 and BmKn2) from the venom of the scorpion, Buthus martensii (Kasch). The 70 amino acid residue Peptide BmKn2 has antibacterial activity against Gram-positive bacteria S.aureus, M.luteus, B.subtilis, and Gram-negative bacteria E.coli, and P.aeruginosa.

A recent study, published in July PLoS ONE issue, has reported that this Peptide BmKn2 exhibited higher antibacterial activity against clinical antibiotic-resistant strains such as Methicillin-Resistant Staphylococcus aureus (MRSA).

Dr. P. Kumarasamy