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Microbiology Commons

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Amit Kumar, DVM, MS, PhD

2013

Articles

Articles 1 - 4 of 4

Full-Text Articles in Microbiology

Adhesion Of Fusobacterium Necrophorum To Bovine Endothelial Cells Is Mediated By Outer Membrane Proteins, Amit Kumar Dec 2012

Adhesion Of Fusobacterium Necrophorum To Bovine Endothelial Cells Is Mediated By Outer Membrane Proteins, Amit Kumar

Amit Kumar, DVM, MS, PhD

Fusobacterium necrophorum, a Gram-negative anaerobe, is frequently associated with suppurative and necrotic infections of animals and humans. The organism is a major bovine pathogen, and in cattle, the common fusobacterial infections are hepatic abscesses, foot rot, and necrotic laryngitis. The species comprises two subspecies: F. necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme. Bacterial adhesion to the host cell surface is a critical initial step in the pathogenesis, and outer membrane proteins (OMP) play an important role in adhesion and establishment of certain Gram-negative bacterial infections. The means by which F. necrophorum attaches to epithelial or endothelial cells has not …


Production Of Nitrogen-Based Platform Chemical: Cyanophycin Biosynthesis Using Recombinant Escherichia Coli And Renewable Media Substitutes, Amit Kumar Dec 2012

Production Of Nitrogen-Based Platform Chemical: Cyanophycin Biosynthesis Using Recombinant Escherichia Coli And Renewable Media Substitutes, Amit Kumar

Amit Kumar, DVM, MS, PhD

BACKGROUND:Cyanophycin (CGP) is a sustainable polymer that can be converted to a derivative with reduced arginine content, or to completely biodegradable poly-aspartic acid, which can substitute for non-biodegradable polyacrylates. In nature, it is produced by most cyanobacteria; however, these microbes are not suitable for large-scale production due to slow growth and low polymer content. RESULTS: Cyanophycin synthetase gene (cphA) from Anabaena variabilis ATCC 29413 was PCR amplified and cloned into Escherichiacoli.Differentrenewablemediacomponents,suchassoybeanmeal,potatowastesandcorn-derivedzein hydrolysate, were evaluated for their feasibility for CGP production at shake flask level. The optimized conditions were then tested in a 7 L bioreactor; a maximum cell weight of …


Characterization Of Fusobacterium Necrophorum Isolated From Llama And Alpaca, Amit Kumar Dec 2012

Characterization Of Fusobacterium Necrophorum Isolated From Llama And Alpaca, Amit Kumar

Amit Kumar, DVM, MS, PhD

Fusobacterium necrophorum, a Gram-negative, anaerobic bacterium, is an opportunistic animal and human pathogen that causes a variety of infections termed necrobacillosis. There are 2 subspecies of F. necrophorum (subsp. necrophorum and subsp. funduliforme) that differ morphologically and biochemically and in virulence. Leukotoxin, a secreted protein, is considered to be the major virulence factor. In camelids, F. necrophorum causes a variety of infections, generally involving the lips, tongue, pharynx, interdigital spaces, foot pad, larynx, mandible, or maxillary bones. The objective of the current study was to characterize the presumptive Fusobacterium isolates from a variety of necrotic infections in llama (Lama glama) …


Outer Membrane Proteins Of Fusobacterium Necrophorum, Amit Kumar Dec 2012

Outer Membrane Proteins Of Fusobacterium Necrophorum, Amit Kumar

Amit Kumar, DVM, MS, PhD

Fusobacterium necrophorum, classified into subsp. necrophorum (Fnn) and subsp. funduliforme (Fnf), is frequently associated with necrotic infections of animals and humans. The outer membrane proteins (OMP) of many Gram negative bacteria play an important role in bacterial adhesion and establishment of infection. The OMP profile of F. necrophorum has not been well characterized. We analyzed OMP of bovine strains of Fnn and Fnf and human strains of F. necrophorum. Electrophoretic separations of extracted OMP of Fnn and Fnf strains of cattle showed a total of 19 and 20 protein bands, respectively. The most prominent protein band was 40 kDa in …