Nick Oswald

I started Bitesize Bio on a Macbook on my kitchen table in 2007 while in my 7th year of working as a molecular biologist in biotech. My aim was to share the know-how that I had acquired from the school of hard-knocks in the lab, so that others could learn from my mistakes and small victories. Nowadays my mission is to facilitate the gathering of hardcore know-how from whole spectrum of bioscientists and share it here on Bitesize Bio to create a super-mentor that any bioscientist can turn to for much-needed guidance.

Articles by Nick Oswald:

The Easier Way to Write a PhD Thesis

Without good planning and preparation, writing your thesis can be a nightmare. Here are some tips on how to make the process a whole lot easier.

10 Aug 2016 Writing, Publishing & Presenting

Antibiotics Used in Molecular Biology

Antibiotics are used in a wide range of techniques in molecular biology. My aim with this post is to provide an easy reference to some of the main ones used in molecular biology, their mechanisms, range and working concentrations. I hope you will find it useful. Your Personal Antibiotics Reference Guide *Abbreviations: Gm(+/-)=Gram positive/negative; My=mycoplasma;…

04 Aug 2016 DNA / RNA Manipulation and Analysis

The Essential PCR Troubleshooting Checklist

Routine PCR? Let’s be honest, there’s no such thing. Even with the simplest PCR reaction things can go wrong, so you need to have a good checklist of ideas for PCR troubleshooting and rectifying the problem. Today I have brainstormed all of the ways I can think of to approach problems with standard PCR reactions.…

27 Jul 2016 PCR, qPCR and qRT-PCR

E.coli Electroporation vs Chemical Transformation

This is the first in a three part series on the transformation of E.coli. By the end of this you should be an expert on E.coli transformation and on which strains to choose for different applications. If you’re already an expert, I hope it’ll be an enjoyable refresher for you. In either case, please comment…

26 Jul 2016 DNA / RNA Manipulation and Analysis

PCR Problems? Try an Additive

You’ve tried all the usual stuff, and checked the primer sequences twice, but still can’t get that PCR fragment amplified. It’s time to enter the strange world of PCR additives. Over the years a variety of additives have been shown to enhance PCR reactions in certain situations. Here is a summary of some of the…

09 Jul 2016 PCR, qPCR and qRT-PCR

Perfectionism: Are you on the downward spiral?

Do you fear failure every time you do an experiment? Do you feel constantly stressed about obtaining poor results? Do you feel personally culpable when an experiment goes wrong? If you answered “yes” to any or all of these questions, you may be suffering from perfectionism. For a scientist, this is a particularly damaging trait…

09 Jul 2016 Personal Development

Why Do Enzymes Have Optimal Temperatures?

Every biologist is familiar with the profile of the rate of an enzymatic reaction versus temperature as shown in the figure. We know that enzymes from E. coli or warm-blooded animals tend to have an optimum around 37°C, while those from thermal vent bacteria have much higher optimal temperatures. Surprisingly, I find that many biologists…

09 Jul 2016 Protein Expression & Analysis

What’s The Problem With Ampicillin Selection?

Ever wonder what those small colonies, like satellites, surrounding a larger E. coli colony on your LB with ampicillin plates were? Or why, when you picked that colony, it never had the plasmid you just transformed? Well, it’s because those satellite colonies are “protected” from the ampicillin by the big colony. Read on for more… Ampicillin…

09 Jul 2016 DNA / RNA Manipulation and Analysis

The Basics: How Phenol Extraction of DNA Works

Phenol extraction is a commonly used method for removing proteins from a DNA sample, e.g. to remove proteins from cell lysate during genomic DNA preparation. It’s commonly used, but not commonly understood. If you want to know how it works so you can show off to all of your friends… read on. The basic protocol…

09 Jul 2016 DNA / RNA Manipulation and Analysis

How to Shut Off Background Lac Expression in LB

Here’s a tip that you may find useful if you are expressing proteins in E.coli using a lac promoter-based expression system, e.g. pET, in LB medium (L-broth). Lac expression systems are typically induced in the lab using IPTG (isopropyl-beta-D-thiogalacto- pyranoside), which is a non- hydrolyzable analog of lactose, the natural inducer of the lac operon.…

09 Jul 2016 Protein Expression & Analysis