37
votes
Accepted
What was the breakthrough behind the “sudden” feasibility of mRNA vaccines in 2020?
Answering my own question after reading the 2018 Nature review article “mRNA vaccines — a new era
in vaccinology”
The resources and motivation engendered by the COVID-19 pandemic are a major factor in ...
- 985
11
votes
Accepted
What are the difficulties/challenges against developing a coronavirus vaccine?
There are multiple challenges presented, and many of those are not limited to coronavirus vaccine.
As mentioned above, it just takes time. Before a vaccine can be used in patients, clinical trials ...
- 150
7
votes
Is PCR a DNA cloning technique?
Short answer
All of your sources are correct as they are not mutually exclusive. PCR is used to isolate and amplify DNA to yield small quantities of pure target product. Gene cloning can subsequently ...
- 52.6k
7
votes
Accepted
Why is a gene for a fluorescent protein used rather than one for an enzyme that produces fluorescent molecule?
GFP has a lot of advantages:
The detection of the fluorescence works directly and doesn't need a lysis step or the uptake of a reagent.
Fluorescence can be detected directly using a fluorescence or ...
- 52.5k
7
votes
What is synaptic bias?
Often artificial neurons are created with conventions that zero is "rest" and 1 is "threshold". The unit starts at 0, and when it reaches 1 it will send an input to all of its targets and be reset ...
- 46.5k
6
votes
Accepted
Why are there two abrupt changes in the genome sequencing price curve?
This graph from the Broad's Opinionome blog (ugh) is somewhat more annotated:
As noted elsewhere, the precipitous drop in 2007 is almost certainly due to maturing next-gen sequencing (NGS), in ...
- 9,701
5
votes
Accepted
Is it possible in modern biology to make any person's identical twin (or genetical clone) using his DNA?
I will assume that by "identical twin", you refer to "clones". Individuals who share the same genetics but of course do not necessarily share the same womb. I won't pay much attention in detail ...
- 68.3k
5
votes
Plasmids for high school students?
I'd suggest looking at the Terms and Conditions for nonprofit use, here is a screenshot of where it is on the webpage:
Look at this form that they link to for legal understanding of what they mean:
...
- 10.5k
4
votes
Why is a gene for a fluorescent protein used rather than one for an enzyme that produces fluorescent molecule?
There are no genes that I know of that encode proteins, more specifically enzymes, that will catalysed the production of a fluorescent compound from intermediates present in the average cell. ...
- 26.3k
4
votes
Accepted
Why is western blotting used to confirm positive ELISA HIV tests?
One reason a Western blot is more specific than an ELISA - even one using the same set of antibodies - is background.
Antibody-linked colorimetric reactions aren't completely on/off. There's always ...
- 1,574
4
votes
What is the easiest way to measure a human body surface area?
How cost efficient does it has to be? Do you want these data to be comparable to another study?
Fundamental issues
What do you call surface area?
The interior of the guts (interior of the mouth, ...
- 68.3k
4
votes
Accepted
Using nanodrop for analysing biological samples other than nucleotides
The Nanodrop is a generic UV-visible spectrophotometer. According to the manufacturer, the latest model can measure absorbance from 190 to 850 nm. Its dynamic range is also very good: from about 0.1 ...
- 715
4
votes
Protein electrophoresis
The problem statement says all the proteins have the same molecular weight but does not say how many amino acids they have. It does say how many cysteine amino acids each has, but not how many other ...
- 9,083
4
votes
Accepted
Transformation of a multicellular organism
Your inference is basically correct. The Agrobacterium acts as a vector for a plasmid containing the genetic construct one wishes to introduce into the plant genome. A medium containing a large number ...
- 940
4
votes
Why are there two abrupt changes in the genome sequencing price curve?
The graph is in contradiction with the data in the Excel spreadsheet the same webpage provides (https://www.genome.gov/sites/default/files/media/files/2019-06/Sequencing_Cost_Data_Table_Feb2019.xls (...
- 1,915
4
votes
Accepted
Problem with joining the gene of interest into the open plasmid when their lengths are not the same
From your question I suspect that you are thinking of DNA as being a very rigid molecule — it isn't.
Double stranded DNA is reasonably flexible and a useful mental model would be to think of this ...
- 5,613
4
votes
Accepted
Which was the first restriction endonuclease to be isolated?
The restriction endonuclease (RE) isolated from E. coli K strain was a type I restriction endonuclease, identified/characterized by Meselson and Yuan1 in 1968. Type I REs are site specific, but ...
- 12.9k
4
votes
Accepted
What is the minimum Ct value that you would consider indicates no gene expression?
Can't you just do a negative control and use that to calibrate?
Alternately, run the DNA from your PCR on a gel with a positive control indicating expression. Literally zero expression should mean ...
- 10.5k
3
votes
How can I describe running a solution four times through a chromatography unit (in an instruction)?
I would continue to use inject to describe loading samples into the liquid chromatography system and replace
chromatograph the RNAase solution four times.
with ...
- 1,305
3
votes
Mathematical Biology Jobs/Prospects?
Off course you can! Here are career paths for you as per my limited knowledge:
BioStats
There are lot of applications in this domain. For example in Microarray Gene Expression or Proteomics analysis ...
- 1,631
3
votes
Fermentation of bananas
Fruit Moonshine is quite desirable :)
Peel the bananas. Good workflow here:
http://www.moonshiners.club/banana-moonshine-recipe/
It takes considerable work especially in large quantities. ...
- 1,309
3
votes
Accepted
Is PCR a DNA cloning technique?
Short answer
The Oxford English Dictionary is quite clear on this. For the verb clone there are two meanings:
Biology To propagate (an organism or cell) as a clone.
Molecular Biology To make copies ...
- 22.8k
3
votes
Will genetically modified food affect our health?
Genetic engineering is a technology not a trait.
In general, genetic engineering and genome editing are as safe as conventional breeding and mutagenesis (introducing thousands of random mutations by ...
- 1,127
3
votes
Role of calcium chloride during competent cell preparation
Although we do not have any conclusive proof about how $CaCl_2$ works, the suggested mechanism is much similar to what you have suggested. When $CaCl_2$ dissociates in aqeous solution, $Ca^{2+}$ ions ...
- 14.1k
3
votes
Accepted
Mass production of bacteria
The fed batch culture is a means of bacterial production that is used in industrial setups. Nutrients are fed into the chamber with controlled ideal conditions for growth of a particular species of ...
- 558
3
votes
Accepted
Selection of recombinant host by color selection method
The Z gene you are talking about should be lacZ that encodes the $\beta-$galactosidase, which is made from $\alpha$ and $\omega$ peptides. Neither peptide is functional by itself.
$\beta-$...
- 242
3
votes
A doubt in biotech question
Endogenous just means that it is naturally occurring in the organism:
http://www.dictionary.com/browse/endogenous
endogenous cytoplasmic defense gene is a general description of a gene that is ...
- 911
3
votes
Accepted
What promoter is required for expression of a human protein Y in bacteria?
Canadianer has very deftly enabled me to arrive at the answer with knowledge I already had. I attempt to explain the same here.
We know that eukaryotes and prokaryotes have different RNA polymerase (...
- 71
Only top scored, non community-wiki answers of a minimum length are eligible