There is a growing body of evidence that many of the thousands of prescription and over-the-counter medications ultimately make their way into water bodies and drinking-water supplies. Typical wastewater treatment plants may not be effective at removing pharmaceuticals. This is because there are no regulations limiting the release of these substances in the environment and, as a result, the needed treatment technology may not have been investigated or implemented. Knowing the best treatment practices for removing pharmaceuticals from wastewater is important for protecting drinking-water supplies as well as organisms in marine and aquatic environments because many pharmaceuticals are designed to be effective at low concentrations. A new study shows that removal of pharmaceuticals from wastewater is possible, even at very low concentrations, depending on the specific treatment process, according to researchers reporting in Environmental Science: Water Research & Technology (January 2020). See also: Environmental toxicology; Freshwater ecosystem; Marine ecology; Water pollution; Water resources; Water treatment

Researchers have developed polymeric materials that are able to kill multidrug-resistant bacteria without inducing drug resistance or toxic side effects, according to a report in Nature Communications (March 2018). The polymers, known as guanidinium-functionalized polycarbonates, contain a polycarbonate backbone to which a hydrophobic spacer group carrying a guanidinium C(NH₂)₃⁺ group is attached. The positively charged guanidinium group enables the polymer to be prepared as a water-soluble salt as well as to bind to the negatively charged cell walls of bacteria. After attachment, the polymer penetrates and crosses the cell membrane and then precipitates the proteins and genes in the cytoplasm, effectively killing the bacteria. Antibiotic resistance in bacteria is a serious problem worldwide, with the World Health Organization in January 2018 reporting 500,000 people with suspected antibiotic-resistant infections in 22 countries. See also: Antibiotic; Antibiotic resistance; Antimicrobial agents; Drug resistance; Infectious disease; Polymer

It is estimated that 1 gram of soil can be inhabited by up to 10⁹ microorganisms and approximately 60,000 bacterial species. Moreover, soil harbors a vast reservoir of antimicrobial agents, and soil-dwelling bacteria have played a key role in the introduction of antibiotics to treat infectious diseases. Because these resilient bacteria not only produce antibiotics but also are exposed to other antibiotics produced by surrounding strains in the soil, they have developed diverse mechanisms to survive the toxic antimicrobial compounds created around them. Importantly, these mechanisms of robust resistance to numerous classes of antibiotics often resemble the mechanisms of resistance identified in clinical pathogens, including those that infect humans. Thus, scientists are attempting to find possible correlations between antibiotic resistance in soil bacteria and in infectious agents in humans. If correlations can be found, investigators might be able to predict future signs of clinical resistance to certain antibiotics, providing clinicians with methods to circumvent any potential resistance that may emerge. See also: Antibiotic; Antimicrobial agents; Antimicrobial resistance; Bacteria; Clinical microbiology; Drug resistance; Infectious disease; Medical bacteriology; Microbiology; Pathogen; Soil; Soil microbiology

Antisense drugs are gene-based molecules that inhibit the synthesis of proteins (including proteins that cause specific diseases) by binding to the ribonucleic acids (RNAs) responsible for their formation. Specifically, these drugs are single-stranded short polymers of RNA or deoxyribonucleic acid (DNA), termed oligonucleotides, designed to contain part of the noncoding strand of messenger RNA (mRNA), which is a molecule involved in translating DNA into protein. Antisense medications are therefore capable of hybridizing with and inactivating the mRNA, preventing the associated gene from producing the unwanted protein. With their anticancer, antiviral, and anti-inflammatory therapeutic capacities, these drugs have been applied in the treatment of various genetic disorders and infections, including diabetes, rheumatoid arthritis, cytomegalovirus retinitis (a virally caused form of blindness that occurs often in AIDS patients), asthma, hypercholesterolemia (a genetic derangement of fat metabolism characterized by very high levels of cholesterol in the blood), and numerous cancers. Research is also being conducted on patients suffering from Parkinson's disease and Huntington's disease to determine whether antisense therapy can mitigate the effects of these conditions. See also: Biotechnology; Deoxyribonucleic acid (DNA); Disease; Gene; Genetic engineering; Oligonucleotide; Protein; Ribonucleic acid (RNA)

Soil harbors a vast reservoir of antimicrobial agents. In fact, approximately 80% of all clinically implemented antibiotics are derived from soil-dwelling bacteria. However, many bacteria have evolved methods to evade the effects of various antibiotics and thus have acquired resistance to these chemical substances. Today, the increasing resistance of many common disease-causing bacteria to antibiotics is a global health crisis. Therefore, scientists are seeking to develop new antibiotics that can overcome the resistance capabilities of numerous pathogenic bacteria. Arylomycins are considered to be among the most promising of these new compounds. See also: Antibiotic; Antibiotic resistance; Antibiotic resistance in soil bacteria; Antimicrobial agents; Bacteria; Infectious disease; Medical bacteriology; Microbiology; Pathogen; Public health; Soil; Soil microbiology

A compound found in cranberries, called cranberry proanthocyanidin (cPAC), when used in combination with antibiotics, such as tetracycline, prevents resistance to antibiotics in Escherichia coli and Pseudomonas aeruginosa, according to researchers reporting in the journal Advanced Science (May 2019). In addition, the combined use of antibiotics with cPAC inhibits biofilm formation, another a route toward antibiotic resistance. This type of synergy—whereby one substance that does not normally produce a desired effect makes a second substance significantly more effective—is called potentiation. See also: Antibiotic; Antibiotic resistance; Biofilm; Cranberry

The biotechnology used in the creation of genetically modified crops is being expanded to encompass the bioengineering of plants that contain therapeutically important proteins and molecules that can be utilized in the manufacturing of pharmaceutical drugs. Often termed "pharming" (a blending of the words pharmaceutical and farming), this process allows scientists to transform a plant's genome via the insertion of a foreign deoxyribonucleic acid (DNA) molecule that carries the genetic information for a pharmaceutical substance. Once the new DNA is inserted, the cultivated plant can produce (by use of its inherent protein-making machinery) large quantities of active pharmaceutical ingredients. Then, these ingredients can be extracted from the plant and processed into a pharmaceutical formulation that has medical application. Specific products include medicinal drugs, vaccines, therapeutic proteins, antibiotics, antibodies, and diagnostic compounds. In other words, the methodology creates a scenario in which farmed plants and crops act as miniature bioreactors or factories to produce pharmaceuticals in an efficient and economically viable manner. See also: Agricultural science (plant); Biologicals; Biotechnology; Deoxyribonucleic acid (DNA); Genetic engineering; Genetically engineered plants; Genetically modified crops; Medicine; Pharmacology; Pharmacy; Protein