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Showing: 241 - 260 of 1028 results
  1. How to Be an Excellent Trainee

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    Blog Post
    ...rotation students, joining a new lab at any career stage, learning a new technique while visiting a lab, ...technical mentorship from a ‘bench mentor’. In some instances, the bench mentor is also the scientific mentor...mentor…but usually the bench mentor is a staff scientist, postdoc, lab manager, technician, or a graduate...there any relevant papers you can read prior to the start of your training? These could serve two purposes...and other educational resources to help you get started!) Are there protocols you can familiarize yourself...materials (maybe a step in the protocol you don’t understand the purpose of, or a different way of doing something...your bench mentor if they have time to answer outstanding questions you have, well before experimental ...
  2. Avoiding the Dark Side of Fluorescent Protein Fusions with mOX FPs

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    Blog Post
    ...is also an avid long distance runner, gardner, and cook.      Lindsey M. Costantini received her PhD in...by guest bloggers Erik L. Snapp and Lindsey M. Costantini. "You underestimate the power of the Dark Side...non-cytosolic protein functions properly? We suggest starting by using the newly published oxidative optimized...used in various combinations. For example, with standard fluorescent microscope filter sets, users can ...when utilizing an optimized moxFP as opposed to standard FPs. The increase in signal is not due to a brighter...systems should strongly consider using moxFPs over standard FPs for the reasons listed above. In addition,...susceptible to the oligomerizing effects of many standard FPs. The moxFPs are now available through Addgene...
  3. Targeted Mutagenesis with EvolvR

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    Blog Post
    ...method requires constant turbidity of the culture, so bacteria must be grown in a turbidostat. Only mutate...spectinomycin resistant phenotype in bacteria. While there are many known spectinomycin resistance mutations...only uncovered novel resistance genotypes, but also provide a better understanding of the key residues ...of wild-type E. coli, while only increasing the standard mutation rate seen during DNA replication by 120... than the original nCas9, while increasing the standard mutation rate by only ~2-fold over nCas9 levels...allow researchers to trace the progeny of a single starting cell. Additionally, multiplexing of guides allows... feature which they used to generate bacteria resistant to both spectinomycin and streptomycin, but could...
  4. A Deep Dive into BioBuilder

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    Blog Post
    ...about Synthetic Biology. Can you tell me where to start?” is a question more and more students are asking...and joy, rather than a perfect lesson plan or outstanding test scores.  As a result, Kuldell launched the... high school teachers to boost interest and understanding around the engineering of biology. Participating... principles to biological systems. Today, what started in Cambridge with a handful of local high school...BioBuilder curriculum is now taught in almost every state in the U.S. and in more than 30 countries around...recognized platform in March to exhibit projects at any stage of completion, from pitch to prototype. Last year...breathalyzer to pesticide breakdown, production of fire-resistant housing insulation, and cleaning up salt runoff...
  5. Sweating the Small Stuff: Details in the Lab

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    Blog Post
    ...grateful, I started setting aside 3-5 minutes to sit quietly at my bench before the start of any experiment... you’re much more likely to make a mistake. When you make a mistake, you’re more likely to be stressed...experiment failing because of a small, avoidable mistake. Or worse, when you're trapped in a pattern of ...same goes for your workflow. Next time you make a mistake, instead of silently vowing never to do that again...workflow, or your physical setup - to prevent the mistake, just like you would change variables to fix a ...a failed experiment.  For example, I used to constantly underestimate time needed to prep for an experiment...experiment. What fixed it was not trying even harder to start earlier, but simply moving all my prep work to the...
  6. Special Delivery: Fluorophore Targeting for FRET Studies

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    Blog Post
    ... an Assistant Professor at Brigham and Women’s Hospital. Biochemists often struggle to understand how ...molecular distances (see Table). However, proper control experiments are needed to establish the dynamic...acceptor (D/A) distance at which 50% FRET occurs. b Range corresponds to calculated D/A distances for observed... FRET can be used to derive a precise physical distance between the donor/acceptor fluorophores (Stryer...labeling. Fluorescent proteins (FPs) are the gold standard for genetically-encoded FRET donors (Fig. 1). ...especially since the potential rewards could be substantial: Plasmid tRNA Synthetase Expression Host ...reviewed in [Yan & Bruchez, 2015]). To get you started, two robust orthogonal labeling strategies are ...
  7. Five Popular Model Organisms, Part 2

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    Blog Post
    ...Justin Ng and Alyssa Cecchetelli Science is a constantly evolving and demanding field, requiring a variety...of biological research that has defined our understanding of biological processes and developments. Model...used as a model organism for over 60 years with a status as the most studied prokaryotic organism. With ...growth rate, small size, and low cost, it’s understandable why E. coli is the most popular bacterial organism...settings. One of its most attractive features is its stability and easily obtainable growing conditions. As a...thrive with or without oxygen. Additionally, its status as a Biosafety Level 1 microbe makes it a perfect... biofilms, and much more. Because of it’s BSL-1 status, E. coli can be used as a model to relate these...
  8. Harnessing Bacterial Toxins for Allelic Exchange

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    Blog Post
    ...chloramphenicol-resistant strains, we have also included versions with gentamicin-resistance (amplified from...disrupt expression of a gene with an antibiotic resistance cassette. This leaves a “scar” in the chromosome... in the creation of scarless mutations, both in stand-alone systems (Jiang et al., 2013), and those which...be accomplished by selecting for an antibiotic resistance marker from the vector (abR, Figure 1). The resolution...This vector contains sacB, an chloramphenicol resistance cassette, and the R6K origin of replication to...replicated in the recipient, the only antibiotic resistant colonies isolated are those where the allelic ...conjugate that well. This is because in these circumstances, the conjugation can be so inefficient, that...
  9. Choosing the B(right)est Fluorescent Protein: Aggregation Tendency

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    Blog Post
    ...between studies is substantial (e.g, the poor performance of mRuby2 is detected by Constantini et al (2015) ...selecting a bright fluorescent protein and a photostable fluorescent protein. In the third post of this...modules that fail to homodimerize in cells. To understand how well fluorescent proteins approach this ideal...dimerization tendency, as is present in EGFP. Constantini et al, (2012) developed a cell-based assay that...tagRFP does not act as a true monomer in cells (Constantini, 2012), whereas it was previously concluded to...chosen FP in your cell type of interest before starting your experiments.  Selecting a non-oligomerizing...CytERM with mTurquoise2 and dTomato, which are established monomeric and dimerizing FPs respectively, are...
  10. Summer SciComm Series: Cognitive Load

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    Blog Post
    ...scicomm bandstands: cognitive load.  Cognitive load The Wikipedia definition of cognitive load states: “cognitive...mental thought and effort your audience needs to understand what you’re communicating. While I’m sure that...of knowledge new to mankind. And you probably understand how much faster it would be for an expert in ... are asking your audience to take on, just to understand you at the most basic of levels.  Concepts This...lot of science communication is helping people understand new concepts. You hopefully are aware that this...foundational concepts (that they often don't!) to understand us, or being able to connect one concept to another...for your audience. I ask myself that question constantly (and so should you!)  Amount of information and...
  11. Plasmid-based Recombinant Monoclonal Antibodies: What They Are and Why You Should Be Excited About Them

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    Blog Post
    ... for antibody expression. If starting from a protein sample (for instance, affinity purified antibodies...then be tested for antigen binding. If starting from an established hybridoma line, the antibody can be ...from a plasmid or from an integrated sequence in a stable cell line. The genes encode the heavy chain and...traditional hybridomas.  First, the long-term stability, consistency between batches, and molecular definition...and sequences for antibodies are not shared. For instance, through open plasmid sharing, the CRISPR community...antibodies, modify antibody function, improve antibody stability, and design tools that we haven’t even imagined...10.1038/521274a Begley CG, Ellis LM (2012) Raise standards for preclinical cancer research. Nature 483:531...
  12. Plasmids 101: The Wide World of Natural Plasmids

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    Blog Post
    ...organisms can’t use. Other plasmids offer resistance to toxic substances like heavy metals or pesticides, enabling... Blog Plasmids 101: Antibiotic Resistance Genes Antibiotic Resistance: An Old Solution but a New Problem...natural plasmids. Created with BioRender.com. Resistance (R) plasmids: microbial defense Genes allowing...its host. For example, cells with a penicillin resistance plasmid can grow in spite of a hostile Penicillium...fungus trying to kill them off. While antibiotic resistance-mediated selection is indispensable for cloning...cloning work, antibiotics and plasmid-encoded resistance to them are the tools of a millennia-old microbial...like colicin typically also carry the necessary resistance genes to help cells survive their own secretions...
  13. Antibodies 101: Multiplex Immunofluorescence

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    Blog Post
    ...combined in one step. As with standard IF, you will need to start with a fixed sample. Depending on... antibodies. The general process is similar to standard immunofluorescence, but with some extra considerations...photobleaching or by stripping out the antibodies, then start over with the next target: add the new primary, ... will need to include a marker like the Hoechst stain for the nuclei. (See Brewer et al, 2022 for a sample...Abcam's sample protocol is a good place to get started.  One important consideration when deciding whether...magenta), anti-AnkyrinG (green), and Hoechst nuclear stain (cyan). Panels C1-C3 show magnified detail of the..., many of the same considerations apply as for standard IF. However, there are a few specific considerations...
  14. Plasmids 101: Optimizing Plasmid Yields

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    Blog Post
    ...time, plasmid prepping is a breeze. You get your stab from Addgene, streak for single colonies, sub-culture... genotype, as these mutations improve plasmid stability and yield. If a plasmid is prone to recombination...plasmids with inverted terminal repeats. We use NEB Stable to transform and prep high quality DNA that contains...recombination, but are also endA+. endA encodes a thermostable periplasmic endonuclease that can sometimes ...of common E. coli strains. Increase the volume Starting with a larger culture volume can improve plasmid...performing filter based plasmid prepping. Be sure to stay within the recommended range of the filter or you...growth conditions. For many high copy plasmids, standard LB broth and antibiotic concentrations will work...
  15. Troubleshooting and Optimizing a Western Blot

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    Blog Post
    ...forget to start it, the samples can actually migrate into the buffer — so it’s better to start over if ...consider using an unstained protein ladder, which will run a bit more true to size than a stained ladder. Unstained...transfer worked with Ponceau S staining or other reversible protein staining immediately after your transfer... Check transfer with Ponceau red stain or other reversible stain* Roll out all of the bubbles in...dilutions of your sample or protein of interest to understand the dynamic or working range of a given reagent... runs to optimize or troubleshoot.   Before you start… Mark your membrane! Membranes look the same from... amounts of protein, make sure your reversible staining method of choice is appropriately sensitive. If...
  16. What's the Best Way to Elute and Store Your Plasmid DNA?

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    Blog Post
    ...of preference, and it will be stable for years. Plasmid DNA can be stable at 4°C or even room temperature...answer: yes. This last step will influence the stability of your sample over time and determine which experiments...effectively use the DNA. pH and DNases affect DNA stability Figure 1: So many choices! What to do? ... The main factors that can affect DNA stability in solution are pH and DNase contamination.  Extreme... favors the breakage of the hydrogen bonds, destabilizing the molecule and favoring the separation of ... be able to store your sample without having substantial degradation and which experiments you can use... buffer is the best buffer for preserving the stability of your preparation for a long time. Tris buffer...
  17. 10 Ways to Share Your Science!

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    Blog Post
    ...office is a good place to start. It’s not unusual to find science writers who started out as graduate students...skills. So, where can a graduate student or post-doc start? The good news is there are more opportunities than...Here are my recommendations on some ways to get started sharing your science with the community. Some of...father or your best friend who isn’t a scientist, start. If they don’t seem all that interested in the details... You’ll know you are on the right track if they start asking you questions. Remember that people like ...often, failure. It’s useful for non-scientists to understand not just the details of your science but also...written by practicing scientists. 3)   Consider starting up your own twitter feed or talking about and ...
  18. Antibody Validation for Flow Cytometry

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    Blog Post
    ...have only been stained with secondary antibodies, showing the level of background staining. All antibodies... orthogonal approach to understand the relationship between antibody staining intensity by flow cytometry...different depending on the sample and target type. To start the validation process, one must first confirm that...permeabilized in 0.1% saponin. 400,000 cells were stained with the indicated Synaptotagmin-1 antibodies and...CoraLite® Plus 647 secondary antibodies. Antibody staining was quantified using the Attune NxT Flow Cytometer...Cytometer with representative images showing the staining intensity in the KO population (pink histogram)...maximize the separation and reduce any background staining. This can include using: different blocking reagents...
  19. Fluorescent Proteins 101: Green Fluorescent Protein (GFP)

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    Blog Post
    .... Now GFP and its fluorescent derivatives are a staple in the lab. GFP is used in research across a vast...consisting of 238 amino acids derived from the crystal jellyfish Aequorea victoria. It has a fluorescent...that increased the fluorescence intensity and photostability of GFP. This also shifted its major excitation...to GFP and new iterations of fluorophores are constantly being engineered. Table 1 below lists a few common...Known Function S65T Increased fluorescence, photostability, and a shift of the major excitation peak to...Increases quantum yield for BFP Y145A and H148D Stabilizes the structure of Cerulean derivatives F99S,...GFP and other fluorescent proteins have become a mainstay in molecular biology. Scientists can easily utilize...
  20. Transferable Skills Guide: Teamwork

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    Blog Post
    ...products of teams: Watson, Crick, & Franklin, Meselson-Stahl, Hershey-Chase...Who was I to dispute history? And... I happily embrace (and admittedly, I may have started that nickname myself). I have my own little Product...shipped; Chiara, the tech transfer expert who understands the somewhat complicated Material Transfer Agreement... kit pages. No single person could possibly understand every nuance of how kits work at Addgene, but...and others, we have updated our kit process substantially and have plenty of ideas for further improvements...biochemist, a geneticist, a microscopist, a biostatistician, and that one golden-handed technician who ...Andrew, the team’s founder, to create a mission statement in the first few meetings and we’ve volunteered...
Showing: 241 - 260 of 1028 results