What is the purpose of Expasy?
It is an extensible and integrative portal which provides access to over 160 databases and software tools and supports a range of life science and clinical research areas, from genomics, proteomics and structural biology, to evolution and phylogeny, systems biology and medical chemistry.
What is ProtParam used for?
ProtParam (References / Documentation) is a tool which allows the computation of various physical and chemical parameters for a given protein stored in Swiss-Prot or TrEMBL or for a user entered protein sequence.
What is theoretical pI?
Written by Damian Costello. The pI (isoelectric point) refers to the pH at which the net charge of a protein is zero. We calculate the theoretical pI by using the pKa’s of amino acids and summing the net charge across the protein at a given pH, searching with our algorithm for the pH at which the net charge is zero.
Which tool is accessed by ExPASy platform?
The protease digestibility prediction tool in ExPASy is called PeptideCutter,8 which can be accessed directly at http://web.expasy.org/peptide_cutter/.
What is GRAVY value of protein?
The GRAVY value for a peptide or protein is calculated as the sum of hydropathy values [9] of all the amino acids, divided by the number of residues in the sequence.
What does the pI of a protein tell you?
The isoelectric point (pI) is the pH of a solution at which the net charge of a protein becomes zero. At solution pH that is above the pI, the surface of the protein is predominantly negatively charged, and therefore like-charged molecules will exhibit repulsive forces.
How do you predict pI of protein?
The charge state of the protein at a given pH is the sum of the negative and positive charges on the charged residues and the C-terminal and N-terminal residues of the protein. To determine the pI value for the protein, the pH value at which the charge state of the protein is equal to zero must be found.
Where do the instructions for protein synthesis come from?
It begins with the sequence of amino acids that make up the protein. Instructions for making proteins with the correct sequence of amino acids are encoded in DNA. Figure 6.4. 1: Transcription and translation (Protein synthesis) in a cell. DNA is found in chromosomes.
How are tRNAs used in the synthesis of proteins?
The two amino acids carried by the first two tRNAs are bind together with help from the ribosome and using cellular energy in the form of adenosine triphosphate (ATP). The above steps repeats until there are uncoupled codon sequences on the mRNA – thus the chain of amino acids grows longer.
When do polypeptide chains form in protein synthesis?
Polypeptide chains are formed during the translation process of protein synthesis. These polypeptides may or may not fold into proteins at a later stage. However, the term ‘protein synthesis’ is used even in the scientific community and is not incorrect.