It would have been impossible to actively develop the science of nature and study the interaction of living beings with our environment without specialists, known as biologists. They not only explore the properties and laws by which the living world develops but also determine the diversity of plant species. The biologist collects material on topics, studies it, conducting experiments and developing technologies for the practical application of the data. A biologist is not any person who has gained higher education in this sphere, but a scientist who has rich experience in the study of nature with published scientific works.
For a more detailed study of individual branches of biological science, scientists undergo special classes. Then, botanists study vegetation, zoologists – animals and birds, physiologists and anatomists – human features, and microbiologists – microorganisms. Of course, there are other areas in biology.
The main workplace of the biologist is clinics, biochemical laboratories, pharmacological production, research scientific centers, agricultural enterprises, the food industry and environmental protection organizations. Sometimes, biologists become university lecturers with fundamental knowledge.
Some biologists are not satisfied with the knowledge gained and visit hard-to-reach and scarcely inhabited places, they continue to look for new plants and representatives of the animal world.
WHAT ARE THE MAIN FEATURES OF A BIOLOGIST?
The most important feature of the biologist is the enduring love of nature and the constant desire to study it, enriching its knowledge and making a contribution to this science. He must be purposeful, disciplined and attentive. It is inherent in logical thinking and analytical mind. The study of nature will require a biologist persistent and concentrated. Being away from comfortable conditions requires excellent health and physical stability from a biologist. He must have excellent vision and color perception. Equally important is the memory and especially visual, so that when an object of the study appears in the field of view, he can determine whether he saw it earlier or not.
WHAT ARE THE MAIN DUTIES OF A BIOLOGIST?
The main activities performed by biologists are research, practical experience, new experiments. These works require knowledge of the planning of the event, the preparation of all necessary materials and equipment. He must carefully register devices readings. If necessary, make adjustments to the plan of the experiment. The biologist must be able to conduct a detailed analysis of the final data, competently compile an appropriate report on the problem being dealt with. Studying the data obtained by other scientists of the world, introducing advanced experiences, using today’s technologies and equipment, the biologist must constantly engage in the multiplication of qualifications. As a teacher in universities, he should be able to transfer intelligibly biological knowledge to students.
While documentaries showing penguins raising their young in the middle of perilous blizzards captivates many, in reality, most of our interactions with birds are quickly forgotten, with perhaps the exception of mild annoyance when seagulls steal our chips at the beach. These same seagulls often enjoy a free meal at landfill sites and then clean their feathers in our drinking water reservoirs. As birds are global residents, occupying diverse ecological niches, what happens in Australia doesn’t always stay in Australia – many of these species migrate to Siberia and back, connecting the opposite ends of our planet.
Melbourne’s Western Treatment Plant provides one of the most important habitats for wild birds in Australia (see here and here). This human sewage treatment facility extends over 10,500 hectares, roughly the size of Disney World, and 500 megalitres of wastewater are treated every day. The last stages of wastewater treatment consist of a series of aerating lagoons where microorganisms that require oxygen are used to clear remaining pollutants. These lagoons can be a key refuge for over 250 bird species, especially during dry periods where water is scarce in various parts of Australia.
Our research shows that active (expressed, and therefore functioning) antibiotic resistance genes are present in bacteria from all birds we analysed, from ducks in Melbourne to penguins in Antarctica.
The Western Treatment plant is a major site, not only for birds and birdwatching, but also for research activities. Birds at this site are regularly sampled for viruses by members of our team, and recently these birds served as models to study avian virus communities where we used a new method of high-throughput RNA sequencing (RNA-seq) (often called “metatranscriptomics”). RNA-seq generates an enormous amount of information that can be explored in various ways, and our research group has applied this method to investigate whether the microbes in those birds were carrying antibiotic resistance genes – whereby accumulation of these genes leads to multidrug resistance and thus, a superbug. As comparisons, we also sampled from three other locations in Australia – a remote lake in the interior, an island off the coast of Tasmania, and Western Port Bay near Melbourne city – along with penguins from two colonies in Antarctica.
The discourse around antibiotic resistance is becoming more and more important. The ramifications of this public health emergency imply that, in the near future, infections such as gonorrhoea will no longer be treatable. That is, the repercussion of this run-of-the-mill STI will be persistent and potentially serious disease, rather than mild embarrassment and a doctors’ visit. This global increase in antibiotic resistance is largely a consequence of overuse of antibiotics by humans and in animals, as growth promoters in food for animals, and a desperate attempt at maintaining the health of plants that we eat (for more information, see here). The result of all this is an increased load of antibiotics in the environment. Alarmingly, bacteria can easily transfer antibiotic resistance genes to each other via horizontal gene transfer, even if they are from different species. Antibiotic resistance is now one of the biggest threats to global health.
Our research shows that active (expressed, and therefore functioning) antibiotic resistance genes are present in bacteria from all birds we analysed, from ducks in Melbourne to penguins in Antarctica. Interestingly, we found nearly five times more resistance genes in birds in the wastewater treatment facility than in birds from all other sites. Antibiotics and antibiotic resistant bacteria commonly end up in sewage systems, and other studies have shown that they are not entirely removed during the wastewater treatment process. Although tempting to point to human waste as the cause of the higher resistance gene burden seen in these birds, it is important to note that we only observe a correlation, and a larger sample size is needed before we can be certain. Of course, it is likely that additional factors contribute to the higher resistance gene burden in these birds, including the composition of their “resident” microbial communities (i.e. microbiomes).
We also sampled penguins from two colonies, one next to a small base supporting a maximum of 16 people during summer only, and one next to a base over twice the size which houses people all year round. Although our penguin samples contained relatively few resistance genes, sure enough, the penguin colony next to the larger research base contained more resistance genes than the more remote colony; again suggesting that human impact is allowing antimicrobial resistant bacteria to persist in natural environments, even in the remotest locations.
Penguins and other wild birds are unlikely to depend on antibiotics, so why should we care whether they carry superbugs? Humans, ecosystems and wildlife are intrinsically linked, according to the ‘One Health’ concept (defined by the World Health Organization). Microbes can hitchhike on birds and return to the human food chain, for example, via water systems. Overall, it is crucial to limit the antibiotic resistance problem by halting the excessive use of antibiotics. Birds serve as sentinels of human impact on the environment and tell us a lot about how antibiotic resistance genes are spread and maintained in the environment, like the canary in the coal mine. The coal mine is antibiotic resistance, and the canary is… well… birds.
Early-life dietary nutrition can profoundly affect individual developmental fate and disease prevention. For example, the presence of absence of royal jelly determines whether the larvae of female honey bees develop into a queen (presence of jelly) or a sterile worker (absence of jelly). In a recent review article published in Clinical Epigenetics, we have reported important roles of specific diets in protection of environmental pollution-induced genetic/epigenetic disorders through the regulation of gene expression even when the DNA is not altered.
Epigenetics may be one of the most important molecular mechanisms linking environmental stimulation, fetal programming, and adulthood phenotype.
Epigenetics and pollution
Epigenetics is an important additional aspect of the central dogma of molecular biology and reflects the interactions of the genome with its environment. Epigenetic changes affect gene expression without any changes to the underlying DNA sequence. The epigenome refers to the complete description of all epigenetic modifications across the genome, among which DNA methylation and histone modifications are the most important.
The mammalian epigenome experiences two major cycles of elimination and reconstruction including the periods of gametogenesis and early embryogenesis, during which the epigenome is vulnerable to environmental factors (see figure below).
Environmental pollutions, including ambient air pollution (e.g. particulate matter, smoking, polycyclic aromatic hydrocarbons), hormone-disrupting chemicals (e.g. bisphenol A, vinclozolin, persistent organic pollutants) and heavy metals (e.g. arsenic, cadmium, lead) can seriously affect human health, especially during prenatal and early postnatal life.
The epigenetics diet
Tollefsbol’s lab coined the term “epigenetics diet” in 2011. It refers to a class of bioactive dietary compounds such as isothiocyanates in broccoli, genistein in soybean, resveratrol in red grapes and other commonly consumed foods, which have been shown to modify the epigenome leading to beneficial health outcomes. The epigenetics diet can inhibit tumor progression through modulation of epigenetic-modifying enzymes such as DNA methyltransferases and histone deacetylases as well as certain noncoding RNAs.
For our recent article, we reviewed recent advanced studies that some bioactive compounds may also counteract or attenuate the damage to the epigenome caused by environmental pollutions. For example, dietary supplementation with methyl donors (such as vitamin B12, folate, choline, and others) and the isoflavone genistein can reverse epigenome dysregulation induced by bisphenol A, a hormone-disrupting chemical of public health concern. B vitamins might avert the loss of DNA methylation induced by air pollution. Dietary folic acid supplementation has been shown to prevent the adverse effects caused by heavy metals.
We believe that epigenetic agents could be potentially used to counteract environmental pollution-induced epigenomic defects. In our article, we provide cautions about potential environmental toxins and chemicals in certain foods such as pesticides in fruits (e.g. strawberry) and leafy greens (e.g. spinach), bisphenol A in plastic containers of foods and beverages, dioxins in fatty foods, polycyclic aromatic hydrocarbons when meat is grilled or smoked at high temperatures and mercury in certain seafoods (e.g. king mackerel and swordfish). Those exposures, especially during early development, may lead to profound impacts on later-life health/disease consequences for the child via epigenetic mechanisms.
Epigenetics may be one of the most important molecular mechanisms linking environmental stimulation, fetal programming, and adulthood phenotype. Due to their reversible nature, epigenetic modifications are becoming an attractive therapeutic target.