Besides this, other physical parameters are also vital in ensuring the optimum function of enzymes, such as temperature and humidity. These are only the basic components of a cell culture, other chemicals may be added for other functions

Yeast

Yeast is a widely used eukaryotic unicellular organism as it is one of the model organism in microbiology. It has various species, with Saccharomyces cerevisiae being the most common species used in the research field. It is also one of the biological systems recommended by the iGEM so you might wish to use it someday. For Saccharomyces cerevisiae, they are able to grow anaerobically with the supply of glucose, maltose or trehalose as their carbon source. Ammonia or urea is needed as their nitrogen source, together with the amino acids. Histidine, glycine, cysteine, and lysine are, however, not readily used. S. cerevisiae does not excrete proteases. Sulphur, from amino acids methionine and cysteine or dihydrogen phosphate ion is slaos needed. To ensure the proper functions of the enzymes in the cell, metal ions like Mg and Fe is also needed. biotin and vitamin B₅ be needed for the full growth of yeast.

Virus

The culture of viruses requires the culture of cells of mammalian, plant, fungal or bacterial origin as hosts for the growth and replication of the virus. Whole wild type viruses, recombinant viruses or viral products may be generated in cell types other than their natural hosts under the right conditions. Depending on the species of the virus, infection and viral replication may result in host cell lysis.

Animal cell

Animals cell is usually cultivated with a more precise temperature and humidity control, which is typically, 37 °C, 5% CO₂ for mammalian cells. Depending on the source of the cell (the organ from which the cell is extracted from), different nutrient may be required. One of the common source of such cultivation medium is from the serum from animals blood, such as the bovine calf serum. Since animal is such broad family consisting hundreds upon thousands of species, only a handful of cell lines are well characterized from some selected species is available commercially. These cell line may be originated from the same species but of different organs or have different mutations to it (eg. HeLa immortal human cell line), therefore, it is important to read the name of the cell lines carefully.

HeLa cell line is a great example of an animal cell line. Originated back from 1951,it was from a women that unfortunately died of cervical cancer. However, this cell line was found to be immortal and duplicate at a much higher speed than normal, so it was began to be used as a standard research cell line. Till now, approximately 20 tonnes of HeLa cells are produced.

Plant cell

Plant cell cultivation is the action to grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition. Plant cultivation is extremely important as it allows for genetically identical plants to be produced rapidly without the need of seedlings, so that the desirable traits can be kept across generations.

It allows for the plant to…...

• quickly matures
• regenerate the whole plants from plant cells that have been genetically modified
• produce sterile plant that greatly reduced chances of transmitting diseases, pests, and pathogens
• produce from seeds that have very low chances of germinating and growing, i.e. orchids
• clear pathogens and to quickly multiply these plants as 'cleaned stock'

It is crucial for the plant cell culture to grow under completely sterilized environment, therefore, even the air flow in the vicinity should be sterilized by laminar flow cabinet. As plant is autotrophs that rely on light for energy source, itis important to regulate the light source, intensity and duration of the light exposure. Suitable hormones(eg.Auxin) should be added to promote the growth of the plant too.