Biologists study life on many different levels. For example, a cellular biologist is concerned with the most basic unit of life, the single cell, whereas an evolutionary biologist may investigate the origin and genealogical history of a particular species of plant or animal life. The molecular biologist is concerned with understanding the biological phenomena of life at the molecular level. Molecular biology is a multifaceted discipline of recent origin, having emerged in the 1980s from the related fields of biochemistry, genetics, and cell biology.
Basic and Applied Research
A molecular biologist might investigate the genetic basis of a disease, analyzing the gene or genes suspected of causing the disease at the molecular level by using the biochemical technique of DNA sequencing. Genes code for proteins; that is, a particular gene contains the molecular information for producing one particular protein. A gene is expressed through the process of transcription . The DNA of the gene is transcribed by a protein known as RNA polymerase. Some genes are expressed frequently, others rarely or only during special times in development. Thus, a molecular biologist might also seek to understand the regulation of gene expression by studying how and when a gene's RNA message (mRNA) appears.
The mRNA resulting from gene expression is the blueprint for the protein. Ribosomes, the cell's protein synthesis factories, translate the mRNA (read the message) and assemble the protein. After translation , a protein may be modified by covalent attachment of carbohydrates and lipids to particular amino acids. A molecular biologist might seek to determine the three-dimensional structure of a modified protein using techniques like X-ray diffraction and nuclear magnetic resonance.
In addition to carrying out basic research, molecular biologists may also work in applied research. Using recombinant DNA technology, for example, molecular biologists have created economical vaccines against deadly diseases. The molecular biologist often works at the frontier or cutting edge of a discipline. The rewards of such work include the thrill of intellectual discovery and the opportunity to conduct independent research. Also, the efforts of molecular biologists can bring great benefits to society.
To prepare for a career as a molecular biologist, the student should begin by taking a broad selection of science and math courses in high school. Typically, such a course of study would include biology, chemistry, and physics, as well as geometry, algebra, and calculus. Good communication skills are very important for a scientist, so English and public speaking should not be neglected. At college, the student may wish to pursue a field of study involving biology or chemistry as a major, with an emphasis on laboratory training.
Usually about four to five years of study are needed to satisfy the requirements for an undergraduate (bachelor's) degree. Time for specialization comes at the graduate level. At this point, students should begin to focus their curiosity and choose a major area of interest, such as biochemistry, biophysics, genetics, or cell biology. They should also begin to look for a university that has an excellent reputation for research in the area of choice. Then, the student must seek out a particular laboratory and research advisor for real hands-on training and experimentation.
Two degree tracks are typically offered in graduate school: a master's and a doctoral (Ph.D.) program. On average, a student may earn a master's degree in molecular biology in roughly three years; earning the Ph.D. degree may require four to six years of work. Many pharmaceutical and biotechnology companies actively recruit scientists at the master's level who have training in molecular biology techniques. Students who have obtained a Ph.D. degree in molecular biology commonly undertake postdoctoral training: two to four years of additional study and research. Traditionally, only students interested in academic or government careers pursued postdoctoral studies; however, today many private companies offer one-and two-year postdoctoral positions as a means of attracting top scientific talent.
The annual salaries of molecular biologists can range from $20,000 to $150,000 or more, and are influenced by many factors, such as education (master's versus doctoral degree), experience (just beginning or a seasoned veteran), field of expertise ("hot" fields pay better), employer location (big city or small town), and the local supply of and demand for trained life scientists. Typically, industry positions come with somewhat higher salaries than academic or government positions; however, job security in industry may be tied to the financial success of the company. Academic and government positions may offer more intellectual independence, but sometimes lower salaries. The demand for well-trained, creative molecular biologists in government, industry, and academia continues to grow as our knowledge of life's basic processes deepens.
see also Geneticist; Laboratory Technician.
Samuel E. Bennett
and Dale Mosbaugh
Molecular biology is a branch of biology that has been growing in importance since the 1940s. It developed out of the sciences of genetics and biochemistry. Genetics is the study of heredity , the process by which certain characteristics of an organism are handed down from parent to offspring. Biochemistry is the study of chemical compounds and processes in organisms. Molecular biologists seek to explain biological events by studying the molecules within cells. They are especially interested in the molecular basis of genetics and inheritance and the production of proteins. Proteins are large, complex molecules that are an essential part of all living cells.
Most molecular biologists are involved in research and development. Some conduct basic research to expand knowledge without the direct aim of benefiting humans. Others may conduct applied research, which is used to benefit humans directly. Applied research generally focuses on issues important to the health, agricultural, and environmental sciences.
At the turn of the twenty-first century, some molecular biologists are involved in a very important study, the Human Genome Project . This international research program aims to identify all of the approximately 30,000 genes of humans. Molecular biologists are also involved in related investigations of the genetic makeup of several nonhuman organisms. These include Escherichia coli (a microscopic organism found in the human gut), the fruit fly, and the laboratory mouse.
Many molecular biologists are employed by county, state, and federal agencies. Also, they may be employed by private industries such as a pharmaceutical corporation, an animal vaccine supply company, or a laboratory doing tests for doctors and health departments. At the beginning of the twenty-first century, emerging job opportunities for molecular biologists include environmental and pollution control companies and the biotechnology industry. The biotechnology industry uses molecular biology research to improve agricultural crops, develop new tests for disease screening, and develop new drugs. Also, some molecular biologists work at universities and colleges. They teach classes, train students in how to perform research, and conduct their own research in their particular area of interest. An important part of the research is writing up the results for publication. Publication of research allows new information to be shared with the scientific community. Also, publication is important in obtaining grant funding for future research projects.
At the high school level, persons interested in becoming a molecular biologist should study math, chemistry, physics, biology, English, writing, and computer studies. Although there are career opportunities for molecular biologists with bachelor's degrees, most professionals have either a master's or doctoral (Ph.D.) degree. College-level course work generally includes biology (microbiology, genetics, ecology , and so on), chemistry, physics, and computer science.
see also Genes; Genetics.
Cosgrove, Holli R., ed. Encyclopedia of Careers and Vocational Guidance, 11th ed. Chicago: Ferguson Publishing Company, 2000.
Morange, Michel. A History of Molecular Biology. Cambridge, MA: Harvard University Press, 1998.
The Year 2000 Grolier Multimedia Encyclopedia. Danbury, CT: Grolier Interactive Inc., 1999.
Experiences in Molecular and Cellular Biology. Emporia State University. <http://www.emporia.edu/biosci/exmolcel.htm>.