Thursday, July 26, 2012

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

Saturday, July 21, 2012

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

Wednesday, July 18, 2012

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

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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/

Thursday, July 12, 2012

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

Monday, July 9, 2012

Novel Vaccines for Diet Induced Obesity

A recent study conducted by Keith N Haffe, President and Chief Scientific Officer of Braasch Biotech LLC  assessed the effectiveness of two somatostatin vaccinations, JH17 and JH18, in reducing weight gain and increasing weight loss in mice. This research work has recently been published in BioMed Central’s open access journal, Journal of Animal Science and Biotechnology,

A chimeric-somatostatin vaccines made of modified somatostatin causes the body to generate  anti-somatostatin antibodies that subsequently increasing energy expenditure and promote weight loss.

For details see:

Journal of Animal Science and Biotechnology 2012, 3:21 doi:10.1186/2049-1891-3-21

- Dr. P. KUmarasamy

Advanced Course in Immunology,

The AMERICAN ASSOCIATION OF IMMUNOLOGISTS'


Advanced Course in Immunology,


Massachusetts Medical School










Register Today for the
2012 AAI Advanced Immunology Course


Register – Registration Deadline: July 13, 2012


Directed by Leslie J. Berg from the University of Massachusetts Medical School, the AAI Advanced Course in Immunology is directed toward advanced trainees and scientists who wish to expand or update their understanding of the field.

Leading experts will present recent advances in the biology of the immune system and address its role in health and disease. Topics include:

  • Anatomy of the Immune Response

  • Innate Immunity

  • Molecular and Cellular Mediators of Inflammation

  • B Cell Development

  • T Cell Development

  • Lymphocyte Memory

  • Mucosal Immunity

  • Immune Response to Pathogens

  • Tolerance

  • Tumor Immunology

  • Immunotherapeutics

  • Vaccines


View the complete schedule and faculty listing.



Wednesday, July 4, 2012

An anaesthetist's dubious record!

ANAESTHETISTS BEWARE OF YOSHITAKA FUJII'S FAKE RESEARCH PAPERS

Fujii, in his 19 year career as an anaesthetist, has published 249 research articles in various medical journals. He was serving at Tokyo Medical and Dental University, the University of Tsukuba, and also recently at Toho University in Tokyo.

It all started when John Carlisle, a consultant anesthetist with the South Devon NHS Foundation Trust in the United Kingdom published an analysis of Fujii’s work that found his results to be fishy and cooked-up and he prompted the Japanese Society of Anesthesiologists to conduct an investigation on the validity of his test results.

Focusing on 212 of 249 known Fujii papers, the investigating committee's report submitted to the  Japanese Society of Anesthesiologists on the 29th of June 2012 has found that 172 research papers of Fujii were bogus. Out of these 172 papers, 126 were totally fabricated (without any work been done). The committee could not conclusively determine if there had been fabrication for another 37 papers. Only three were found to be genuine!

Previously, a German anesthesiologist named Joachim Boldt is believed to hold the dubious distinction of having such a dubious record of 90 papers!

Fujii has surpassed this record by 36 more papers to his 'credit'!