Final answer:
An antibacterial drug kills bacteria, and an antibiotic is one example that targets specific parts of bacterial cells. A semisynthetic antibiotic is a derivative of a natural antibiotic modified for improved efficacy. Antiseptics are suitable for microbial control on living tissues.
Step-by-step explanation:
The type of drug that kills bacteria is an antibacterial. Examples include antibiotics, which can either be naturally produced by organisms such as molds or can be synthetic, meaning they are chemically created. Antibiotics function by targeting specific parts of bacterial cells, such as cell walls or essential enzymes, without harming the host's cells. They can have a narrow spectrum and kill specific types of bacteria, or a broad spectrum to kill a wider range of bacteria. Given the information that a scientist has modified an antimicrobial compound by chemically converting a side chain, which created a drug that not only kills gram-negative bacteria but now also gram-positive bacteria, this would be considered a semisynthetic antibiotic. Semisynthetic antibiotics are those that are chemically modified derivatives of naturally occurring antibiotics, and they often have improved efficacy or spectrum of activity compared to their natural counterparts. When considering what is suitable for use on tissues for microbial control to prevent infection, an antiseptic is appropriate as it can kill or inhibit microbial growth on living tissues, such as skin, without causing significant harm.