Regulation of mammalian deoxyribonucleotide biosynthesis by nucleotides as activators and inhibitors.

Phospholipase D1 Couples CD4+ T Cell Activation to c-Myc-Dependent Deoxyribonucleotide Pool Expansion and HIV-1 Replication

Quiescent CD4+ T cells restrict human immunodeficiency virus type 1 (HIV-1) infection at early steps of virus replication. Low levels of both deoxyribonucleotide triphosphates (dNTPs) and the biosynthetic enzymes required for their de novo synthesis provide one barrier to infection. CD4+ T cell activation induces metabolic reprogramming that reverses this block and facilitates HIV-1 replication...

Effect of Activators and Inhibitors on Lactase Activities to Determine its Kinetic Model

Accelerated Cytotoxicity Mechanism Screening

By discovering how chemical compounds/xenobiotics cytotoxicity is affected when their metabolic pathways are inhibited or activated, the metabolic pathways that activate versus detoxify chemical compound can be identified. Reactive metabolites contributing to cytotoxicity can also be identified. In this lecture, the pretreatment of inhibitors and activators of xenobiotic metabolizing enzymes as...

Induction of apoptosis in IL-3-dependent hematopoietic cell lines by guanine nucleotide depletion.

Inosine 5'-monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme that catalyzes the conversion of IMP to xanthosine monophosphate (XMP) at the branch point of purine nucleotide biosynthesis, leading to the generation of guanine nucleotides. Inhibition of IMPDH results in the depletion of guanine nucleotides, prevents cell growth by G1 arrest, and induces cell differentiation in a cell-t...

Bacterial metastasis: the host plasminogen system in bacterial invasion.

Several pathogenic bacterial species intervene with the mammalian proteolytic plasminogen-plasmin system. Recent developments have been made in understanding the structure and the virulence-associated functions of bacterial plasminogen receptors and activators, in particular by using plasminogen-deficient or transgenic gain-of-function mice. Bacteria can affect the regulation of the plasminogen...