The increasing resistance of many common disease-causing bacteria to antibiotics poses a global health crisis. However, a powerful compound called teixobactin, belonging to a new class of antibiotics (specifically, a novel class of peptidoglycan synthesis inhibitors), was identified in late 2014. This antibiotic, which was isolated from the newly discovered soil bacterium Eleftheria terrae, holds great promise because, in preliminary tests, numerous pathogenic bacteria seemingly could not develop resistance to it. If further studies and trials indeed prove this antibiotic to be free of resistance, then it will become a major weapon in the fight against a number of serious diseases and infections. See also: Antibiotic; Antibiotic resistance; Antimicrobial agents; Bacteria; Bacteriology; Drug resistance; Microbiology; Public health

Depending on their reactions to the bacteriological dyeing reaction called Gram’s stain, bacterial species are categorized into gram-positive and gram-negative types. Teixobactin has been found to be an extremely potent antibiotic capable of working against the gram-positive group of microbes (which lack an outer cell-wall membrane), including bacteria that cause tuberculosis (Mycobacterium tuberculosis), lobar pneumonia (Streptococcus pneumoniae), strep throat and rheumatic fever (Streptococcus pyogenes), severe diarrhea (Clostridioides difficile; formerly, Clostridium difficile), and anthrax (Bacillus anthracis), as well as Staphylococcus aureus, the bacterium that causes toxic shock syndrome and methicillin-resistant (MRSA) infections. In all studies done so far, gram-positive microbes have never shown any resistance to this antibiotic, and would seemingly need to evolve an outer cell wall to acquire such resistance. (There are no guarantees, however, that some unforeseen route to resistance might not emerge in the future.) Teixobactin is being fast-tracked into preclinical development studies. See also: Anthrax; Anthrax bacillus and the immune response; Clostridium; Human susceptibility to Staphylococcus aureus; Medical bacteriology; Soil microbiology; Staining; Staphylococcus; Streptococcus; Streptococcus pneumoniae (pneumococcus); Toxic shock syndrome; Tuberculosis

Unfortunately, teixobactin does not have any effect on gram-negative bacteria. Therefore, teixobactin will not be available to fight such dangerous illnesses as cholera (Vibrio cholerae), plague (Yersinia pestis), and gonorrhea (Neisseria gonorrhoeae), or infections from pathogenic strains of the common bacteria Escherichia coli and Pseudomonas aeruginosa.