Most of us have some ideas of what proteins are and even can tell some examples by name and function. Fitness enthusiasts & gym lovers usually know about actin or even myosin and their role in muscle contractions. Health-conscious eaters and nutritionists know about ovalbumin, the major protein found in eggs. Careful parents might know that vaccines can contain inactivated bacterial toxins that are actually proteins. Nurses and health-conscious people know that antibodies are proteins, and these are also known as immunoglobulins. Anybody who has ever done a full blood test measuring liver function too might realise that several markers measured are enzymes (things ending with -ase), types of proteins playing important roles in metabolising food. People wanting to measure their telomerase levels know that telomerase is an enzyme too maintaining the end of chromosomes in dividing cells.
The good news: understanding the term proteome is just one step away from understanding what particular proteins or groups of proteins are. A proteome is a collection of proteins present in a particular space and during a particular time point or time period. In living organisms a proteome usually represents all proteins expressed and functioning in a particular ‘place’ (spatiotemporal unit) but this unit can be interpreted on many levels: a single cell, groups of neighbouring cells, groups of types of cells, a volume of bodily fluid like saliva or blood or urine, a particular tissue like muscle tissue, a particular organ like kidney, a particular organ system like nervous system. Concerning the state of the proteome it can be a diseased proteome from a tumour or a healthy proteome from healthy individuals or a healthy control proteome from ‘normal’ neighbouring cells of a tumour. Another flavour of proteomes arise due to the presence of the human microbiome (or microbiota) as the totality of the microorganisms in the human host. Different body parts have different microbiomes and hence there are different microbioproteomes that can be measured, like the oral or gut microbioproteomes.
An all-inclusive human proteome concept can include all the human protein variants. This is a theoretical entity that cannot be detected with the methods available today. A more practical concept is the measurable proteome containing all the proteins that can be detected with the current state-of-the-art method. Here we would like to talk on the qualitative aspects of what a proteome is so avoid mentioning numbers and quantities.
What do we aim to capture with Gen P, our first product? The aim with Gen P is to capture enough proteins of the oral proteome, including both human and bacterial proteins to collect comprehensive data on the most important functional systems and pathways involved.
Let’s finish this post by showing the different cells generating the proteins sequenced and quantified with Gen P. Hope this helps our would be users to understand what qualitatively the oral proteome measured via Gen P. We talk numbers in subsequent posts.