32P, 33P and 35S: selecting a label for nucleic acid analysis

Article Abstract:

Several criteria should determine which radioisotope is used to label nucleic acids; this labelling is a necessary step in many molecular biology research techniques including filter hybridization and DNA sequencing. Three radioisotopes are now available: phosphorus 32 (32P), sulphur 35 (35S) and the recently introduced phosphorus 33 (33P). Detection sensitivity and the desired degree of spatial resolution are the most important factors to consider in choosing which of these radioisotopes to use. Although 32P and 35S will continue to be standard, new uses for 33P will probably soon be developed.

Methods, Usage, Molecular biology, Phosphorus, Phosphorus (Chemical element), Radioisotopes

---

A tetrameric DNA structure with protonated cytosine-cytosine base pairs

Article Abstract:

Cytosine-rich strands of DNA oligomers were shown to form intercalated, double-stranded structures at acid pH. The duplex strands are found to be highly symmetrical, and an energy and molecular dynamics model is compatible with observed nuclear Overhauser effects (NOEs). The intercalated base pair structure has been designated the 'i-motif' and could possibly be a common feature of sequences containing long stretches of deoxycytidine. Tetrads and analogous forms have yet to be investigated for their biological significance.

Research, Oligodeoxynucleotides

---

Breathing room for early animals

Article Abstract:

Atmospheric oxygen enrichment during Neoproterozoic era may have caused the diversification of multicellular animals. According to the carbon isotope hypothesis, increase in the organic carbon burial rate can lead to atmospheric oxygen enrichment. The sulphur metabolism and oxidation in bacteria imply the underlying function of organic carbon burial in oxygen enrichment. Sulphur isotope data on the pre- and post-Neoproterozoic era indicate a gradual increment in organic carbon burial rate.

Reports, Observations, Oxygen, Evolution (Biology), Paleontology, Proterozoic Eon, Transmutation of animals

Similar abstracts:

• Abstracts: Brain-processing limitations and selective pressures for sleep, fish schooling and avian flocking. Survival skills required for predator evasion by fish larvae and their relation to laboratory measures of performance
• Abstracts: Tyrosine kinase-dependent selection of transmitter responses induced by neuronal contact. Structure of an SH2 domain of the p85-alpha subunit of phosphatidylinositol-3-OH kinase
• Abstracts: Cheap date. Finding homes at synapses
• Abstracts: The chemistry of fullerenes. Make or break with fullerenes. Coalescence reactions of fullerenes

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.