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Ornithine decarboxylase (ODC) is an enzyme that initiates polyamine synthesis in human. Polyamines play key roles in cell-cell adhesion, cell motility and cell cycle regulation. Higher synthesis of polyamines also occurs in rapidly proliferating cancer cells are mediated by ODC. As per earlier
Ornithine transcarbamoylase from ovine liver has been purified to homogeneity. Like all anabolic OTCs, the ovine enzyme is a trimer, constituted by identical subunits of 34 kDa. Sequence analysis of the 54 N-terminal residues of ovine OTC shows a high degree of homology with the human enzyme. The
We present here an energetic and atomistic description of how D-ornithine 4,5-aminomutase (OAM), an adenosylcobalamin (AdoCbl; coenzyme B(12))-dependent isomerase, employs a large-scale protein domain conformational change to orchestrate the homolytic rupture of the Co-C bond. Our results suggest
A total of 13 Pasteurellaceae isolates from healthy freshwater turtles were characterized by genotypic and phenotypic tests. Phylogenetic analysis of partial 16S rRNA and rpoB gene sequences showed that the isolates investigated formed a monophyletic group. The closest related species based on 16S
The 26S proteasome is a eukaryotic ATP-dependent protease, but the molecular basis of its energy requirement is largely unknown. Ornithine decarboxylase (ODC) is the only known enzyme to be degraded by the 26S proteasome without ubiquitinylation. We report here that the 26S proteasome is responsible
Intracellular levels of ornithine decarboxylase (ODC) are raised following mitogenic stimulus and in neoplasia. Because lesions of the oral cavity are often difficult to assess histologically, we have determined the value of immunocytochemical detection of ODC as a prognostic indicator in 74
Polycationic compounds, such as poly-L-arginine and poly-L-ornithine (PLO), enhance the nasal absorption of hydrophilic macromolecular drugs. However, the bio availability corresponding to the dose of these enhancers has not been obtained in an open system study, where an administered solution is
The present study demonstrates that biogenic silica fibers (BSF), previously shown to promote skin tumors in mice and more recently to promote the induction of mesotheliomas when injected into the pleural cavity of rats, rapidly induces epidermal ornithine decarboxylase (ODC) activity in SENCAR mice
In this study, polyamine biosynthesis required for cellular proliferation showed elevated levels in neoplastic cells. Putrescine, spermidine, and spermine, as well as the rate-limiting enzyme ornithine decarboxylase, were measured to evaluate differences in tissue concentration in squamous cell
The polyamines putrescine, spermidine and spermine are essential for normal growth and differentiation and the activity of the enzymes participating in their synthesis and catabolism are markedly modified in actively proliferating cells in vitro and in vivo. In some neoplastic cells a good
Tumorigenesis requires increased biosynthesis of polyamines and elevated levels of ornithine decarboxylase, which is the rate-limiting enzyme in the polyamine synthesis pathway. Previous animal studies have noted a marked increase in ornithine decarboxylase after exposure to tumorigenic stimuli and
We selected a 2-difluoromethylornithine-resistant Ehrlich ascites-carcinoma cell line that grows in the presence of 20 mM-difluoromethylornithine. These cells contain 10-20 times the normal amount of hybridizable sequences for ornithine decarboxylase (EC 4.1.1.17) in their genomic DNA. We used these
Six strains of anaerobic, pleomorphic Gram-positive bacilli, isolated from the human oral cavity and an infected arm wound, were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. 16S rRNA gene sequence analysis revealed that the
Mitochondrial carriers are a large family of proteins that transport specific metabolites across the inner mitochondrial membrane. Sequence and structure analysis has indicated that these transporters have substrate binding sites in a similar location of the central cavity consisting of three major
Oral cavity squamous cell carcinoma (OCC) and oropharyngeal squamous cell carcinoma (OPC) are among the most common cancers worldwide and are associated with high mortality and morbidity. The purpose of this study is to identify potential biomarkers to distinguish OCC/OPC from normal controls and to