Friday, 22 June 2018

Scientists Figure Out Why HIV-1C Subtype Replicates Faster

Scientists from India and America have figured out why HIV-1C subtype is more prevalent than other subtypes of the virus.

(Dr. Udaykumar Ranga with the research team)
A team of scientists from India and America have figured out why HIV-1C subtype is more prevalent than other subtypes of the virus.

The human immunodeficiency virus consists of two types HIV 1 and 2 and each one of them has many subtypes. Of them, HIV-1C alone causes half of all the HIV infections globally and nearly all in India.

Researchers have found that HIV-1C can efficiently duplicate an important region of its genome to replicate faster unlike other subtypes. HIV-1C duplicates a region of its Gag protein called PTAP domain to make two copies of this domain.

The study was conducted in a group of HIV positive persons in India. It was found that viral strains of HIV-1C containing two PTAP domains could dominate viral strains containing only one PTAP domain in the blood of eight persons during follow up.

“This molecular trick may have given HIV-1C a big replication advantage over others. Given the dynamic nature of viral evolution, this trick may be transmitted to other slow-witted cousins through ‘viral recombination’ and may make this new molecular trick a universal problem,” explained Dr. Udaykumar Ranga, a scientist at Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bangalore, who led the study.

Dr. Shahid Jameel, a virologist and CEO of Wellcome Trust DBT India Alliance, who was not associated with this study, pointed out that “HIV shows high degree of sequence variation, making it both an interesting virus to study and a difficult one to control through vaccines and drugs.” 

Dr. Akhil C. Banerjea, Emeritus Professor at the National Institute of Immunology commented that “the researchers have found a new motif in HIV that may explain why subtype C can multiply at a faster rate. This study will also allow targeting this motif to control viral replication.”

The research team included Shilpee Sharma, P.S. Arunachalam, Malini Menon, J. Jebaraj, Shambhu G., Chaitra Rao, Sreshtha Pal and Udaykumar Ranga (JNCASR); V. Ragupathy, I. Hewlett (Center for Biologics Evaluation and Research, USA); Ravi Vijaya Satya (GRAIL Inc, USA); S. Saravanan, K. G Murugavel, P. Balakrishnan and (late) S. Solomon (Y.R. Gaitonde Centre for AIDS Research and Education, Chennai). 

This work was supported by Department of Science and Technology (DST). The researchers have published their findings in the Journal of Biological Chemistry.

Journal Reference:

Wednesday, 13 June 2018

New Route To Synthesize Bioplastics Developed

Researchers have developed a new strategy that promises to help expand the scope for production of bioplastics.

A group of researchers has developed a new strategy that promises to help expand the scope for production of bioplastics.

In recent years, scientists and industry have focused on developing bioplastics as a replacement for synthetic ones to help protect the environment. However, bio-polymers produced from materials like starch have found limited applications and their production processes are expensive and generate pollution.

The strategy — developed by researchers from National Institute of Technology (Warangal), SASTRA Deemed University (Thanjavur) and Central University of Jammu — promises to overcome this problem. The process involves use of natural monomers and a bio-catalyst called Novozyme 435. It is a lipase obtained from the yeast called Candida Antarctica.

While preparing oligoesters as part of regular experiments, researchers observed formation of a viscous solution which was behaving very similar to molecular self-assembly: disordered molecules were adopting a defined structure on their own. “This observation motivated us to understand the concept of self-assembly assisted polymerization,” said K. Muthusamy from Sastra University, Thanjavur, co-author in the study.

The new protocol involves two steps. First, bio-based monomers, C-glycosylfuran and diacids, were subject to poly-condensation to form high molecular weight compound in the presence of bio-catalyst. The output was then made to undergo self-assembly assisted polymerization to realize the desired product. Conventionally, vegetable oils, carbohydrates, lignin and cardanol are used for producing bio-based polymers. The process is, however, expensive and not environment-friendly.

“We have used environmental friendly bio-based monomers, C-glycosylfuran derived from monosaccharides and a bio-catalyst. With this approach, we can generate cross-linked polymers and different products with varying properties can be produced by manipulating the design of oligoester. The products may find use for a range of applications in medical and food sectors,” explained study leader Dr. S. Nagarajan of NIT, Warangal, while speaking to India Science Wire.

Converting bio-based monomers into value-added materials is important in sustainable chemistry. “The group has prepared bifunctional monomers and which were converted into polymers using an enzyme-catalyzed reaction. It is an efficient way of generating materials which have potential to make soft materials, and may find applications in near future," commented Dr. Praveen Kumar Vemula from Institute for Stem Cell Biology and Regenerative Medicine, Bangalore who is not a part of this study.

The research team included K. Muthusamy, K. Lalitha, Y. Siva Prasad, A. Thamizhanban, C. Uma Maheswari (SASTRA Deemed University),V. Sridharan (Central University of Jammu) and S. Nagarajan from NIT Warangal. The study, financially supported by the Department of Science and Technology (DST), has been published in journal ChemSusChem.