Microalgae food for honey bees

A microscopic algae ("microalgae") could provide a complete and sustainably sourced supplemental diet to boost the robustness of managed honey bees, according to research just published by Agricultural Research Service (ARS) ...

In cellular biology, mistakes can be good

Mistakes are rarely rewarded. Intuitively, one would imagine that a shoddy typist at an office who keeps generating typos would either quickly lose their job, or at least be overlooked for promotion. The idea that this person ...

Highly efficient, low-cost method developed to reduce DNA errors

DNA only persists through replication—naturally or synthetically. While humans need the genetic material to be reproduced in order to replace old or damaged cells, the ability to replicate DNA in a laboratory setting can ...

Genetic signature boosts protein production during cell division

A research team has uncovered a genetic signature that enables cells to adapt their protein production according to their state. The researchers of the University of Basel's Biozentrum report in Genome Biology that this newly ...

Reproductive genome from the laboratory

The field of synthetic biology does not only observe and describe processes of life but also mimics them. A key characteristic of life is the ability for replication, which means the maintenance of a chemical system. Scientists ...

Histone modifications are the influencers of zygotic genome awakening

The zebrafish is an important model organism in biology. Humans and zebrafish share 70 percent of their genes, and more than 80 percent of human genes associated with disease are known to have a zebrafish counterpart. Additionally, ...

Blue light for RNA control

Messenger RNA molecules contain genetic information and thus control the synthesis of proteins in living cells. Biochemists at the University of Bayreuth and the University of Bonn have now discovered a way to regulate this ...

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Protein biosynthesis

Protein synthesis is the process in which cells build proteins. The term is sometimes used to refer only to protein translation but more often it refers to a multi-step process, beginning with amino acid synthesis and transcription of nuclear DNA into messenger RNA which is then used as input to translation.

The cistron DNA is transcribed into a variety of RNA intermediates. The last version is used as a template in synthesis of a polypeptide chain. Proteins can often be synthesized directly from genes by translating mRNA. When a protein is harmful and needs to be available on short notice or in large quantities, a protein precursor is produced. A proprotein is an inactive protein containing one or more inhibitory peptides that can be activated when the inhibitory sequence is removed by proteolysis during posttranslational modification. A preprotein is a form that contains a signal sequence (an N-terminal signal peptide) that specifies its insertion into or through membranes; i.e., targets them for secretion. The signal peptide is cleaved off in the endoplasmic reticulum.. Preproproteins have both sequences (inhibitory and signal) still present.

For synthesis of protein, a succession of tRNA molecules charged with appropriate amino acids have to be brought together with an mRNA molecule and matched up by base-pairing through their anti-codons with each of its successive codons. The amino acids then have to be linked together to extend the growing protein chain, and the tRNAs, relieved of their burdens, have to be released. This whole complex of processes is carried out by a giant multimolecular machine, the ribosome, formed of two main chains of RNA, called ribosomal RNA (rRNA), and more than 50 different proteins. This molecular juggernaut latches onto the end of an mRNA molecule and then trundles along it, capturing loaded tRNA molecules and stitching together the amino acids they carry to form a new protein chain.

Protein biosynthesis, although very similar, is different for prokaryotes and eukaryotes.

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