Atul Kumar Johri

1991	The Second Congress of Asia and Oceania Society of Comparative Endocrinology New Delhi, India.
1993	Effect of synthetic pyrethroid insecticide fenvalerate on Tetrahymena thermophila National symposium on pesticides Future Scenario. Indian Agricultural Research Institute (I.A.R.I.) Pusa, New Delhi, India.
1994	Use of microbes for the degradation of xenobiotics. National symposium on environment II, National Chemical Laboratory (NCL) Invited Speaker Pune, India.
1994	Cloning of catabolic genes responsible for the degradation of gamma – HCH. Micon-International-94 & 35 Annl. Conf. Asso. Microbiol. India. DFRL, Mysore, India.
1996	Kinetics of degradation of alpha, beta, gamma and delta-HCH by Sphingomonsas paucimobilis A laboratory study. Symposium on Biodegradation of organic pollutants, Mallorca, Spain.
1996	Genetic engineering a tool for the degradation of the aromatic hydrocarbons. National symposium on towards green and sustainable environment, Indian Agriculture Research Institute Pusa, New Delhi, India.
1996	Degradation of HCH isomers by Sphingomonas paucimobilis Molecular Genetics studies. International symposium on subsurface microbilogy (ISSM-96) Davos, Switzerland.
2001	Analysis of biogengineered emulsans from Acinetobacter calcoaceticus RAG-1 and transposon mutants No 18 page 38. Bioengineering meeting Tufts University Science and Technology Centre, Medford MA USA
2001	Engineering of microbial biopolymer analogs. 221 American Chemical Society (ACS) meeting San Diego, California, USA
2002	Effect of Oxygen on Group B Streptococcal Invasiveness. Annual Meeting of Proc Soc., Harvard Medical School, Boston MA USA
2003	Oxygen regulates invasiveness of group B Streptococcus, 103^rd general meeting of American Society for Microbiology May 18-22, 2003 Washington DC. USA
2004	Interaction of Group B Streptococcus with Polarized A549 cells American Society for Microbiology May 23-27, 2004l. New Orleans, LA USA
2006	Proteomics and Group B Streptococcus vaccine development 47 Microbiology conference, 6-8 December, Bhopal India (Invited speaker)
2007	Prediction of eligible vaccine candidates of Group A Streptococcus (GAS) by using bioinformatics approach Poster No:P43, Indo-Australian Biotechnology conference, QIMR, Brisbane, Australia, 7-9 May (2007).
2007	Molecular typing and invasiveness of Group A Streptococcus (GAS) of Indian origin, Poster No: P46, Indo-Australian Biotechnology conference, QIMR, Brisbane, Australia, 7-9 May (2007).
2007	Convener: Symposium on Nanotechnology and its applications in biological science, 14 Dec 2007 Jawaharlal Nehru University, New Delhi, India.
2008	Member executive committee International symposium cancer JNU 2008.
2008	Poster, American Society for Microbiology,general meeting, Boston, USA 2008.
2009	Comparative analyses of of Pili Expression by Streptococcus agalactiae Strains of Indian and United States Origin,American Society for Microbiology, Poster , 105general meeting, Philadelphia, USA 2009.

Research Specialization:

Microbial Pathogenesis, Genomics, Proteomics and Infectious Disease, Microbial Biotechnology, Bioengineering, Biomedical Engineering, Microbial Degradation of Xenobiotics, Nanotechnology.

(1) Vaccine development for Group A Streptococcus and Group B Streptococcus
We would be using reverse vaccinology approach like Proteomics, Genomics and Bioinformatics for vaccine development for Group B Streptococcus and Group A Streptococcus and other infectious microorganisms using dynamic in vitro attachment and invasion system (DIVAS), a system that combines the advantages of controlling bacterial growth by continuous culture methods with perfusion tissue culture and 60mm dishes. We would be studying invasion and adherence of the group B Streptococcus and other infectious microorganisms with various epithelial and endothelial cell lines to fish out role of various proteins and genes that are upregulated and are involved in invasion and adherence by using SDS-PAGE and 2D-gel electrophoresis, MALDI-TOF-TOF, electro spray ionization liquid chromatography tandem mass spectrometry (ESI-LC-MS/MS), and DNA Micro-array etc.

Figure 1: Streptococcus pyogenes on blood agar plates illustrating β-hemolysis

(2) Use of nanoparticles (non-viral vectors) as gene and drug deliver vectors
In principle, the technique of gene delivery involves taking complete or parts of genes that can code specific message and delivering them to selected cells in the body. Such a transfer of plasmid DNA into mammalian cells has posed major challenges for gene therapy. Although viral vectors are attractive in terms of the scientific strategy of exploiting natural mechanism, such systems suffer from inherent difficulties of effective pharmaceutical processing, immunogenicity, scale up and the possibility of reversion of an engineered virus to the wild type. Non-viral vectors, on the other hand, offer some acute advantages as they can safely transfer larger pieces of DNA, they are weakly immunogenic and are easier to use and produce. Consequently, a major focus is now being given at the development and use of non-viral vectors for safe and efficient delivery of gene. We would be using chitosan, gelatin and emulsan as biomaterials for gene and drug targeting in vitro and in vivo.

Figure 2: Transmission Electron Microscopy picture of PVP nanoparticles encapsulating pDNA. Average size of the nanoparticles is < 100nm. The bar represents 200 nm.

(3) Plant microbe interactions
Arbuscular mycorrhiza (AM) is one of the most prominent symbiotic associations between plant root and fungi. These obligatory biotrophic fungi colonize the root cortex and form arbuscules with in the root cortical cells and also develop a network of hyphae which extend into the soil. Phosphate and carbon transfer between the symbionts is thought to occur at the arbuscule/cortical cell interface. The mechanism by which the plant and symbiont benefit from the association are complex, but it is well documented that the AM fungi absorb mineral nutrients (mainly phosphorus) from the soil and transport them to the host plant, while the fungi acquire photosynthates (reduced carbon) from the plant. The transport of phosphorus by mycorrhizal fungi is particularly significant because phosphorus often becomes depleted around roots due to its high requirement and relative immobility in the soil, thus creating a phosphorus depletion zone. In fungi, the plasma membrane H+-ATPase and phosphate transporter are involved in the phosphorous uptake from the soil, its metabolism and transport to the host plant. We are looking for a phosphate transporter gene and interacting partners in P. indica using cDNA and yeast two hybrid library and PCR techniques.

Figure 3: Visual morphological appearance of fungi P. indica (Axenic growth)

Collaborators:

(1) Dr. L.C. Paoletti: Associate Professor of Medicine, Channing Laboratory, Harvard Medical School, Boston, MA, USA

(2) Dr. Philippe Glaser: Director, Genomics Microbial Pathogenesis unit, Pasteur Institute, Paris, France

(3) Dr. N Tuteja: Associate Scientist, Plant Molecualr Biology , ICGEB, New Delhi, India

(4) Dr. Meenakshi Dua: Assistant Professor, School of Environmental Sciences, JNU, New Delhi

(5) Dr. Rino Rappuoli, Global Head, Novartis Vaccine, Italy

(6) Prof. R. Stroud, and Dr. William Harries, Director, Membrane Biology center, University of California, San Francisco, USA

(7) Prof. G.S. Singh Chhatwal, Head, Helmontz Center for Infectious disease, Germany.

(8) Prof. Geeta Mehta: Head, Microbiology, Lady Hardinge Medical College, Delhi

(9) Dr. Dipti Nayyar, Department of Microbiology, Safdarjung Hospital, New Delhi

Group Members:

Abhinay Sharma: (SRF UGC): Serotyping, invasiveness and proteomics analysis of Group A Streptococcus vaccine development

Hemlata: (SRF CSIR): Group B Streptococcus serotyping, invasivness and transcriptional profiling

Hemant Kumar: (SRF CSIR) : Expression and purification and structural analysis of a phosphate transporter (PiPT) from axenically grown endophyte fungus P. indica

Deepak Kumar: (SRF RGNF): Group A Streptococcus serotyping and interaction with lung cell line (A549)

Manoj Kumar: Plant microbe interaction using P indica as a model system

Ruby Sharma (Project Fellow, DST)

Takshila Tripathi (Project fellow, CSIR)

Pratap Singh (SRF, CSIR)

Dr. Suriya Mir

Ph.D. Supervised: (3)

Dr. Rajani Malla : Reader, Tribhuvan University, Nepal
Dr. Vikas Yadav : Post Doctoral Fellow, Tufts University, Boston, USA
Dr. Puja Sharma : Post Doctoral Fellow, Harvard Meedical School, Harvard University, Boston, USA.

Ph.D. Registered: 6

M.Phil supervised: 3

MS supervised: 15

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