Final answer:
Second generation cephalosporins have enhanced Gram-negative bacterial coverage compared to the first generation, while maintaining effectiveness against Gram-positive bacteria. They possess a chemical structure with a β-lactam ring providing resistance to β-lactamases, making them a staple in fighting bacterial infections.
Step-by-step explanation:
The spectrum of coverage of second generation cephalosporins is broader than that of the first generation cephalosporins. While first generation cephalosporins are primarily effective against Gram-positive bacteria and have limited activity against Gram-negative bacteria, second generation cephalosporins have an extended spectrum that includes more Gram-negative bacterial coverage. These antibiotics are often used to treat infections caused by Gram-negative bacteria such as E. coli and Klebsiella species.
Chemically, cephalosporins contain a β-lactam ring which is fused to a six-member ring, conferring increased resistance to β-lactamases. This intrinsic resistance to enzymes that commonly deactivate antibiotics makes them significantly effective against a broad range of bacteria. The development of semisynthetic cephalosporins allows for even greater diversity in chemical alterations and thereby wider antimicrobial activity.
Second generation cephalosporins also have enhanced activity against bacteria that produce extended-spectrum β-lactamases (ESBLs), although they are not as effective as later generations or carbapenems against these resistant strains. The importance of selecting the appropriate generation of cephalosporin for treatment is vital to combat bacteria efficiently and to limit the spread of antimicrobial resistance.