BIOCHEMISTRY II - BSC203

Biochemistry has its roots in medicine, nutrition, agriculture, and natural products chemistry. It covers many other areas as well, but today it is mostly is concerned with the chemistry of molecules found in and associated with living systems, especially the chemistry of these molecules. Biochemists are always trying to break processes down in order to understand how these work, how molecules are created or destroyed and how they relate and affect each other. With the advent of all the modern equipment and computer systems many biochemists also study intact systems and how each system functions and the other structures or processes that may be affected.

This course focuses on developing a greater familiarisation with biochemical molecules.
Students would normally have completed Plant or Animal Biochemistry I, before attempting this module.

Develop a deeper and broader understanding of the chemical compounds that are found in living things.

All organic molecules contain carbon atoms.
Most organic molecules contain both hydrogen and oxygen.
Many contain other atoms as well.
These atoms are arranged in various forms to make up most of the dry weight of living organisms.
Important organic molecules fall into common groups or types,such as proteins, carbohydrates, lipids, nucleic acids, hormones and neurotransmitters.

This course helps you to understand the differences between the groups, and the characteristics of different molecules within those various groups.

Course Duration -100 hours

Course Content and Structure
There are nine lessons in this course as follows:

1. Introduction to Biochemical Molecules
2. Amino Acids
3. Structure of Proteins
4. Protein Dynamics
5. Sugars and Polysaccharides
6. Lipids (Fats) and Membranes
7. Enzymes, Vitamins and Hormones
8. DNA and RNA
9. Laboratory Techniques

Where is Biochemistry Used by Industry?

Biochemistry and biochemical testing have a range of application throughout the health industry, in veterinary and agriculture industries for animal care, breeding and nutrition; for pesticides, soil quality and pasture management. In the environmental field, testing is used to determine contamination, nutrient density and for environmental impact assessment.

A large number of environmental tests are performed in the field using small, portable meters. Water quality testing may be performed with meters and probes that determine salinity and pH, as well as dissolved oxygen and turbidity. The levels of some organic matter may also be determined in the field. Heavy metal testing and testing for contaminating micro-organisms is performed in the laboratory. Experimental procedures that may be used in environmental testing include:

Basic meter readings for pH, salinity and dissolved oxygen
Colourimetric analysis with spectrophotometry for detection and quantitation of particular elements or chemicals in samples.
Microbiology - plates of a gel like substance known as agar are smeared with the sample of interest and incubated generally overnight at either 37C, or at the favoured temperature of the micro-organism being tested for, or suspected of being present. If the micro-organism is present, the plate will have small raised circles on it after incubation; these are made up of colonies of bacteria.
X-Ray Diffraction for mineral analysis
Mid-Infrared Spectrometry for analysis of the minerals, as well as clays, organic matter, carbonate compounds, gypsum and some heavy metals
Isotope testing for information on bodies of water including hydrodynamic properties, origin, inorganic compounds, and vegetation
Liquid scintillation for carbon dating – plants, water and charcoal can all be dated by determining the carbon decay.
Flow Injection Analysis can determine nitrogen levels in plants and soils

Variations on spectrometry can be used to analyse heavy metal contamination

Biochemical and chemical testing can provide farmers with valuable information on the quality of their pastures, crops, soils and water sources. Salinity, a problem in many regions of Australia can be assessed and monitored. Contamination problems can be identified (excessive or poor nutrient load, low oxidation or chemical pollution etc) and the efficacy of control and rectification measures can be monitored. Pesticide and feed compositions can also be examined. Many rudimentary tests can be performed by the farmer, and this can give some basic information so that more precise testing, which is more expensive, can be targeted.

Environmental scientists make use of biochemical analyses to investigate the health of eco-systems as well as the environment as a whole and the impact people have on it. Understanding water sources, nutrient uptake and the impact of animal life all provide vital information on ecosystem health. Biochemical testing is used not only to understand the impact of human endeavour on the environment (environmental assessment, leeching of radioactive elements such as uranium or heavy metals from mines into soils, rivers and groundwater and the path contaminants take from the original source) but can also be used to understand more complex events, such as illness in local populations, which biochemical testing may show is due to bacterial infection for example, or due to a distant environmental impact which has travelled through the environment and then through the food chain.

Medical Science
Biochemistry and biochemical principals are the foundation of medical science. Sub areas of medical science, such as pharmacology, toxicology, clinical chemistry, microbiology, molecular biology and genetics are all rooted in the interactions of biomolecules in living systems. The subspecialty of medicine that deals with biochemistry is known as clinical biochemistry, and focuses on analyses of the body fluids. Specific biochemical tests that may be performed in medical science include:

Quantitation of heavy metals and toxins in the urine, blood, tissue samples, hair etc
Testing for indicators of disease states such as excess blood sugar, high or low hormone levels etc
Arterial blood gases – checking the oxygen levels in the blood as well as blood pH
Immunoassays – using an antibody/antigen reaction to a hormone, enzyme, a particular protein bacteria or virus. This is the type of test commonly used to detect HIV.
Common biochemistry techniques such as blotting (used to detect proteins, DNA and RNA) immunoprecipitation (antibody/antigen reaction to separate out a molecule of interest), electrophoresis, colourimetry, spectrophotometry, types of chromatography such as high performance liquid chromatography and other methods are all routinely used to analyse biological specimens.

Poisons or Toxins
A chemical is poisonous or toxic if it in any way harms a living organism. Not all living organisms find the same chemicals toxic. As a part of evolution, different organisms have adapted to be able to cope with chemicals others find poisonous. An example is alcohol, while it is toxic to many micro-organisms, humans have an enzyme that can metabolise it to non-toxic chemicals, however, our protection is not complete as large amounts of alcohol cannot be dealt with quickly enough, causing the excess to spill into the blood stream, where it has toxic effects, particularly on the nervous system. In this sense, alcohol is still a toxin, when taken in large amounts.

Pharmacology and toxicology are two scientific disciplines that focus on the biochemistry of toxins and poisons. Understanding how a toxin molecule interacts with different biomolecules helps us understand why molecules are toxic, how they affect the body and how to best treat them. Not all drugs that affect a person’s nervous system do so in the same manner, a treatment suitable for depression for example, would be completely ineffective or possibly dangerous in a person with another nervous disorder. Understanding where in the body toxins might be stored (the liver, the fat tissue, the blood etc) can also help in understanding their effects and how to treat them. Toxins in the fat tissue may not be a problem, but if the person or animal drops weight, that fat tissue will be consumed for energy, causing the toxin to enter the tissues and body fluids where it will have harmful effects.

At the biochemical level, toxins interfere with biological processes. They may bind to an enzyme’s active site, stopping a reaction. They may bind to the DNA, triggering a cell to commit suicide, they may alter the DNA, they may bind molecules in clumps, prevent them from getting where they are needed or cause a reaction to proceed too quickly. Some types of poison or toxin include:

Carcinogen – any substance which can make a person more susceptible to cancer causes cancer or makes a cancer progress.
Mutagen – any substance that can cause mutations in the DNA (insertions, deletions, substitutions, larger losses or amplifications)
Teratogen – any substance that causes mutation, deformity, malformation or death of an embryo or foetus. Teratogens may be pharmaceuticals, such as thalidomide or some acne treatments, radioactive elements, some micro-organisms and other organic and inorganic chemicals.

Biochemistry is Changing
Our knowledge of biochemistry is advancing faster than ever before. With new discoveries, come new commercial possibilities that had not even been previously conceived. These changes are making it difficult to predict where the work will be in the future. One thing is certain though; that a knowledge of biochemistry, at any level will be a significant advantage for anyone working with living things, plants, animals or people.