Question

Demonstrate the difference between transcription-translation coupling and separation through application in developmental biology. I suggest the early stages of development, like post-zygote.

Carbon fixation pathways among the bacteria and archaea are said to be diverse. Do living examples exist that could serve as a demonstration of biochemical progression of carbon fixation?

Answer 1

In prokaryotes, RNA polymerase and ribosomes can bind concurrently to the same RNA transcript, leading to the functional coupling of transcription and translation. The interactions between RNA polymerase and ribosomes are crucial for the coordination of transcription with translation. RNA polymerase. RNA polymerase directly binds ribosomes and isolated large and small ribosomal subunits. RNA polymerase and ribosomes form a one-to-one complex with a micromolar dissociation constant. The formation of the complex is modulated by the conformational and functional states of RNA polymerase and the ribosome. The binding interface on the large ribosomal subunit is buried by the small subunit during protein synthesis, whereas that on the small subunit remains solvent-accessible. The RNA polymerase binding site on the ribosome includes that of the isolated small ribosomal subunit. This direct interaction between RNA polymerase and ribosomes may contribute to the coupling of transcription to translation.

Separation through application or reproductive isolation in post-zygote can be through following mechanisms:

Zygote mortality and non-viability of hybridsEdit

A type of incompatibility that is found as often in plants as in animals occurs when the egg or ovule is fertilized but the zygote does not develop, or it develops and the resulting individual has a reduced viability.Hybrid Sterility: hybrid has normal viability but is deficient in terms of reproduction or is sterile. This is demonstrated by the mule and in many other well known hybrids. In all of these cases sterility is due to the interaction between the genes of the two species involved; to chromosomal imbalances due to the different number of chromosomes in the parent species; or to nucleus-cytoplasmic interactions such as in the case of Culex.

Part 2.

Carbon fixation mechanisms:

Reductive citric acid cycle in Chlorobium limicola

Reductive acetyl CoA pathway in methane-forming archana

3-hydroxypropionate bicycle in sulfur-forming bacterial family Chloroflexaceae

Hydroxypropionate-hydroxybutyrate cycle in Crenarchaeota

Dicarboxylate-hydroxybutyrate cycle in archaea classes Thermoproteales and Desulfurococcales.