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It is highly unlikely that there exist any protein that is made from completely identical nucleotide sequences across the entire human population. There will certainly be regions within a gene that are highly conserved, but there is little evolutionary pressure to conserve an entire gene's nucleotide sequence across the population. This is in part due to ...


22

Humans have many variants There is variation. The project I use to help understand this natural variation is gnomAD. Using VarMap and a slightly out of date gnomAD file, I counted 16007805 protein-coding variants across the human genome. This number will only go up over time. Indeed, the 1000 Genome project found that on average each person has between 250-...


12

"Irrational" design in these papers refers to combinatorial mutagenesis, which is put forward as the alternative to "rational" protein design. Rational design involves using existing information about a protein to choose residues to mutate. From Nixon et al.: Alteration of function by rational approaches can be achieved through single-point ...


9

One peptide that comes to mind is the metabolically important reducing tripeptide glutathione — γ-L-Glutamyl-L-cysteinylglycine: This is synthesized from cysteine, glutamate and glycine by reactions catalysed by glutamate cysteine ligase and glutathione synthase: Synthesis of glutathione (GSH) — two subunits of glutamate cysteine ligase (GCL) are shown ...


8

At the whole-gene level, there is likely no absolute conservation of any human protein-coding gene at the population level, though there might be complete conservation between individuals. Keep in mind that most human genes are on the order of tens of thousands of base pairs long, and only a portion of that length encodes functional motifs. There are, ...


7

Let's use an example, a case in point: the best known and plentiful one would be hemoglobin. It is a protein formed through the association of alpha- and beta-globin peptides into dimers or tetramers. The shape is largely a result of the sequence (peptide folding is reproducible, especially with the help of chaperones which may aid the correct folding ...


6

As far as I am aware, there is no known requirement for Cd in mammalian systems, but it is extremely toxic (Waalkes & Goering). It would seem that cadmium is required to get crystals of RBP, and its presence is an artifact of the crystallization process (ref): Pig holoRBP crystals were obtained at 277 K by the sitting-drop vapor- diffusion method, ...


5

From my searches, there is no single resource that includes an atlas of all human proteins produced across all human cell types. However, there are several recent mass spectrometry studies that look at cell-type-resolved proteomes for specific human and mouse tissues that provide some insight into the distribution of proteins across different cells. A Cell-...


5

According to "Drugs: From Discovery to Approval" by Rick Ng. The "rationality" of drug design refers to whether structure is used to inform the design. The Irrational approach: involves empirical observations of the pharmacological effects from screening of many chemical compounds, mainly those from natural products. The active component that gives ...


4

If you scroll down through the uniprot entry you will come to a section with the heading PTM/Processing. From this you can see that the first 18 amino acids are a signal peptide. You can learn more about signal peptides from any good introductory textbook covering cell-biology — alternatively Khan Academy is a good source for learning the basics.


4

I think that you are talking about trans-splicing. This does indeed happen. It is fairly common in protist organisms, though in humans it is quite rare. For more information about how this process works, including mechanisms in vertebrate organisms, see this paper. Here is one model from that last paper for how it works:


3

A curve of this type, showing a bi- or multi-modal distribution, suggests two or more constituent species in the population. In this case this is borne out by further analysis in the paper of different types of secondary structure components anchoring the loop, the peak at low numbers of amino acids reflecting the loops connecting β-strands in anti-...


3

The human body can not store Proteins (technically). BACKGROUND : PROTEIN is a very broad term and there are hundreds and thousands of proteins.[1] Proteins are heteropolymers consisting of amino acids held by peptide bonds. Amino acids : There are 9 amino acids which we need to intake. Phenylalanine, valine, threonine, tryptophan, methionine, leucine, ...


3

Yes The energy released by ATP hydrolysis must be coupled, by enzymes, to some other reaction or process in order to be useful. It isn’t magic. There are ATP-dependent chaperones that assist in protein folding.


3

Spider silk can conduct electricity. Some spiders use this material property of conductivity to capture prey. https://www.ncbi.nlm.nih.gov/pubmed/24323174 So I'm going on the assumption that both electrical lines spanning the web are bare and that they are live, i.e. carrying current. I will also assume that these lines are carrying the same current. With ...


3

I am not an expert on expression of genes from viral vectors, but as I requested the poster to clarify his question I feel an obligation to provide at least a partial answer. The first question to address is whether the mRNA for the protein of interest is expressed in the same way as normal cell proteins. In the case of the lentovirus vectors which are ...


3

In terms of structure: both are composed of amino acids. A peptide is when at least two amino acid are linked together. A protein is composed of multiple amino acids and have a secondary, tertiary and even quaternary structure. In terms of function: larger molecules have more complex functions. Peptides can act as a intracellular or extracellular ligands ...


3

If you have ever used a natural bath sponge, you know that the structure of a sponge's spongin skeleton is great for absorbing water and squeezing that water back out. The sponge's skeleton contains millions of tiny holes, all connected in a massive network of internal tunnels, through which the sponge takes in food and eliminates waste. It feeds by use of ...


3

I was pretty certain @David's comment was spot on, that this was some one-use funny acronym from just this paper, but a search of Google Scholar suggests that it has indeed been propagated sufficiently to have meaning beyond this paper, while also originating, as these things do, in some clumsy one-off usage. One of them gives a clear definition that is ...


3

Cholinesterase inhibitors and plant-pathogenic nematodes While it is true that cholinesterase inhibition does not affect gas exchange in nematodes, it does produce other effects by paralysing motor activity: Inhibition of larval hatching Reduced movement to new roots Impairment of root invasion and feeding Impairment of copulation Acetylcholine also has ...


2

According to PDB (protein data bank — a repository for protein structures) the chromophore must be protected from interaction with water molecules to fluoresce. The chromophore is found right in the middle of the [protein], totally shielded from the surrounding environment. This shielding is essential for the fluorescence. The jostling water molecules ...


2

How do you want to predict function and binding partners without knowing how your protein looks like? The sequence itself contains only limited information. Similar sequences might fold into similar structures with similar functions. These motifs can be used to transfer your knowledge from one protein to another, which might have similar e.g. binding ...


2

There are various proteins sensitive to changes in electric field. More precisely, they are activated by changes in voltage (surrounding the protein), and immersed in water, as all cells are mainly composed of an aqueous solution. You are correct that most charges in the side chains of the proteins' amino acids are 'masked' by the dipole character of water ...


2

From my understanding, operon is a series of genes that are regulated by a single promotor. In many cases genes in an operon form subunits of a protein. Genes in an operon can code for protein subunits, but they can also code for separate proteins. Often an operon will have a few genes responsible for one core function, with other accessory genes that may ...


2

Short answer: Indeed the proteins in our body are based on amino acids from external food sources. BUT, proteins up-taken from food are ALWAYS disassembled first into amino acids, through specialized enzymes, proteases, (for instance Pepsin in the stomach's gastric juices and Tripsin in the pancreatic juices), during digestion, in the alimentary canal, (gut)....


2

Endosome formation. For the sake of keeping this somewhat brief, I'm going to stay somewhat surface level. When a vesicle is endocytosed, it is called a primary endocytic vesicle. When multiple primary endocytic vesicles fuse together, they form a larger entity called an early endosome. Early endosomes can also be called "sorting endosomes" because ...


2

Usually, in such depictions where a species is pointing to a reaction or an interaction, the arrows mean that the species affects that reaction (for example, catalysis by an enzyme ). Generally pointy arrow heads denote positive effect (enhancing the reaction, for example an enzyme) and flat heads denote a negative interaction (repression). An arrow from one ...


2

I'm sure HIV is well studied since as you know it has a small genome and is highly relevent to therapeutic research, but virus regulation can be complicated and not representative of what happens in normal cells. This is why model organisms exist. The yeast Saccharomyces cerevisiae has about 6,000 genes and researchers have systematically deleted nearly ...


2

The problem with coming into bioinformatics from a non-biological background is all too apparent in your question, and very real. You are dealing with a category of object called a protein complex, you suspect that it will be reasonable to exclude a proportion of them, but as you don’t really know what they are (other than at a basic level) you don’t ...


2

what is the accuracy we can predict tertiary protein structure That depends on the protein. If the primary sequence closely matches the sequence of a protein for which the structure is already resolved, then template-based methods to model 3D structure can be used (a.k.a homology modeling). These methods tend to be accurate, as assessed by template-...


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