Amino acids they are called. #YODARULES
Answer:
Several 2',3'-dideoxy-3'-thiapyrimidine nucleosides were studied for their ability to inhibit hepatitis B virus (HBV) DNA replication in a HBV-transfected cell line (2.2.15). 2',3'-Dideoxy-3'-thiacytidine (SddC) and 5-fluoro-2',3'-dideoxy-3'-thiacytidine(5-FSddC) were found to be the most potent anti-HBV compounds of those examined. Both compounds resulted in nearly complete cessation of viral DNA replication at 0.5 microM, as monitored by the absence of both intracellular episomal and secreted viral DNAs. The HBV-specific RNAs were not reduced at concentrations that completely blocked HBV DNA replication, suggesting that the inhibitory target is HBV DNA synthesis. The antiviral action of SddC and 5-FSddC was reversible. The concentration of SddC and 5-FSddC required to inhibit 50% of 4-day cell growth in culture was 37 microM and more than 200 microM, respectively. Unlike 2',3'-dideoxycytidine, these two compounds do not affect mitochondrial DNA synthesis in cells at concentrations lower than that required to inhibit cell growth. In view of the potent and selective antiviral activity, both SddC and 5-FSddC should be further evaluated for the treatment of human HBV infection.
Explanation:
Answer:
Soil is a major source of nutrients needed by plants for growth
Answer: B
Explanation:
Synthesis of an inducible enzyme requires the substrate bound to repressor.
In the synthesis of a specific inducible enzymes, a substrate on which the enzyme acts must bind to the repressor that prevents the synthesis of the inducible enzyme. Example of an inducible enzyme is β-galactosidase in Escherichia coli that degrades lactose and galactose.
The synthesis of β-galactosidase is regulated by a repressor protein, that binds to the region of deoxyribonucleic acid (DNA) that codes for the synthesis of β-galactosidase. If lactose or galactose (substrate) is present, it acts as an inducer which induce the repressor protein from binding to DNA. Hence the enzyme is synthesized
