Search the forum,

reverse

A reverse transcriptase (RT) is an enzyme used to generate complementary DNA (cDNA) from an RNA template, a process termed reverse transcription. Reverse transcriptases are used by viruses such as HIV and hepatitis B to replicate their genomes, by retrotransposon mobile genetic elements to proliferate within the host genome, and by eukaryotic cells to extend the telomeres at the ends of their linear chromosomes. Contrary to a widely held belief, the process does not violate the flows of genetic information as described by the classical central dogma, as transfers of information from RNA to DNA are explicitly held possible.Retroviral RT has three sequential biochemical activities: RNA-dependent DNA polymerase activity, ribonuclease H (RNase H), and DNA-dependent DNA polymerase activity. Collectively, these activities enable the enzyme to convert single-stranded RNA into double-stranded cDNA. In retroviruses and retrotransposons, this cDNA can then integrate into the host genome, from which new RNA copies can be made via host-cell transcription. The same sequence of reactions is widely used in the laboratory to convert RNA to DNA for use in molecular cloning, RNA sequencing, polymerase chain reaction (PCR), or genome analysis.

View More On Wikipedia.org
  1. R

    Reverse Circulation - Sense Check

    Hi everyone, I'm a (somewhat, I hope...) competent DIYer and just want to get some advice if my suspicion on a problem we're having is correct. We had a Megaflo and boiler professionally installed as part of a renovation a couple of years ago. I will add all of the pipework was done by this...
  2. J

    Single pipe systems - can I reverse the flow

    I have a single pipe system retrofitted to a 1930's house. It is powered by a condensing gas boiler. As expected, the radiators get cooler the further they are from the boiler. It occurred to me that if I fitted a "crossover switch" between the punp and the radiators I could send the water...
  3. B

    Possible reverse circulation

    Hi all, we've recently moved into a property and believe there is some kind of backflow in the heating system. (I should say I am a DIYer, and not a great one). When we have our hot water on, the rads get hot over time. I've had floorboards up to see if there is a non-return-valve somewhere...
  4. M

    Reverse circulation Solid Fuel

    I have a Rayburn running my CH and HW, when the boiler is lit, the gravity flow works as it should rises to the cylinder and drops back to the boiler...when the cylinder is hot enough the CH pump comes on and this is where it goes wrong. The pump seems to be pushing the cold radiator water up...
  5. elczkc

    Reverse circulation?

    Just had extension built with 1 new rad and 1 plumbed in towel rail. Since this was connected I have had problems with radiators getting hot with only the HW on. Have checked the motorised TWV and this appears to be OK. I have tested for reverse circulation in an existing upstairs radiator and...
  6. D

    Can I get a reverse hot / cold shower mixer bar?

    Hi, just wondering if anyone knows where I could source a thermostatic shower mixer bar that accepts hot and cold supplies the opposite way around i.e. I’m looking for a mixer where the hot water supply comes in from the right hand side instead of the left. This is to provide a workaround to the...
  7. B

    Reverse Osmosis System- Which Tap?

    Hi, I am considering installing an Undersink RO System, space should not be an issue (I think). We currently have a Quooker (instant boiling water) cylinder and tap installed which we hardly use. I am planning to disconnect and remove the quooker tank from under the sink but the question is...
  8. G

    Reverse flow conundrum

    Hello all, An issue some advice would be great on if you can. Boiler with no leaks, holding pressure fine with a reverse flow FA fault code. If you drain the system and refill, obviously bleeding pump and rads, the whole things runs smoothly for about 5 to 7 days. At a random point it will...
  9. S

    Reverse pipe-sizing

    Hi I'm doing a quote for a customer who currently has a 38kw regular boiler. The size of the house/rads etc. suggests a 24kw or 27kw boiler would be fine. I have done a working pressure test and currently they have a 4.5mb drop over the gas run. I can't see the gas pipe as it runs under the...
  10. M

    Thermostat and Valve Actuator reverse problem

    Hi, I have just installed a new Drayton zone replacement valve , model ZA5. The good news is that the value is working; however, the issue I'm experiencing is that when my thermostat turns the central heating on, the valve moves to the off position and the valve closes and when I turn off the...
  11. T

    Drinking Water - Ceramic Water Filter System vs 6 Stage Reverse Osmosis Water Filter?

    Hi, I am looking to install a new Drinking Water Filter System as water quality is not good at my home. Lots of Lime Scale and Chlorine etc. Which one should I choose? 1. Ceramic Water Filter System 2. 6 Stage Reverse Osmosis Water Filter Appreciate any help in this regard...
  12. T

    The final return tee: always the immersion cylinder return, but is it a standard?

    Hi, Long story short: my boiler (gas, conventional, vented, three port system) has been moved from one side of the house to the other. Previously the immersion cylinder return was the final tee before reaching the boiler, and all worked fine. Now the immersion cylinder return is a few tees...
  13. J

    Reverse circulation new build

    Hi, I'm looking for a little help. I bought a new build and have heating issues since we moved in. The builder wants the installer to resolve the issues, but hes been back now about 5 times and still the issue persists. I was hoping for a little advice. We have 2 circuits 1 upstairs and 1...
  14. mbc0

    Thermostat Working in Reverse?

    Hi, I just replaced my Drayton Cylinder Stat with a Siemens Ram1 stat but it is working in reverse? if I set the stat to a low temp the boiler comes on and vica versa? The stat I took off had two wires connected that had permanent continuity when the stat was off (below actual temp) and then...
  15. F

    Can I bend my reverse J shape kitchen tap to improve the angle of the water flow (photo attached)?

    Hi, my kitchen tap's water flow is hitting the edge of the sink(see photo below)...is it possible to bend the metal so that the angle points towards the middle of the sink rather than the edge? Thanks in advance for you advice!
  16. J

    Reverse Circulation Central Heating

    Hi folks, I am having a problem with reverse circulation. I have attached a photo. The insulated pipe making the tee is the H/W return. Pipe feeding in on the left is the Rad return and the pipe to the right continues to the boiler. Because the pipe to the right has a tight bend i wondered if...
  17. P

    Draining rad circuit in reverse maisonette

    Hi all my first post here so forgive me if this has been answered before. I've quoted to do a boiler swap from an awful Glow worm 18SXI system boiler and tank/cylinder (gravity) to a combi. (gas safe reg 582473 before you ask) the entrance to the flat, current boiler and drain point is on the...
  18. P

    3 port valve problems

    Yet another problem with a new build system which is as follows, System boiler with zoned UFH to ground floor and radiator circuit / water tank upstairs. UFH is controlled by individual room programmers linked to actuators. Radiators / water tank governed by timer, thermostat, fed by 3 port...
  19. N

    Reverse circulation

    I have recently re located the cylinder cupboard (new cylinder) also adding a small radiator at the top of the stairs to the heating circuit , The pump had to be relocated as well. It was under the flooring boards in a bedroom, the pipe work has been extended by about 1 mtr and is still under...
  20. cr0ft

    Reverse Return CH Piping

    Hi all. Does anyone have a good reference with diagrams that explains how this works? Been asked to quote for a system which will require 2x 35KW System boilers and am wanting to install them both onto the same CH pipework. It will be a 3 zone system in a very large property. Spoken with...
Creating content since 2001. Untold Media.

OFFICIAL SPONSORS

OFFICIAL SPONSORS

Back
Top
AdBlock Detected

We get it, advertisements are annoying!

Sure, ad-blocking software does a great job at blocking ads, but it also blocks useful features of our website. For the best site experience please disable your AdBlocker.

I've Disabled AdBlock