Which type of bacteria grow in clusters and are known for being pus-forming?

Staphylococci are a type of bacteria that are indeed known for growing in clusters, resembling bunches of grapes when observed under a microscope. This characteristic clustering is significant because it plays a role in their pathogenicity, or ability to cause disease. Staphylococci are often associated with pus-forming infections, such as boils, abscesses, and other types of skin infections, making them particularly relevant in the context of esthetics and skin care. Their ability to produce pus indicates a strong immune response to the infection they cause, highlighting their clinical importance.

Other types of bacteria mentioned, such as streptococci, bacilli, and spirilla, have distinct characteristics and growth formations; for instance, streptococci grow in chains and are more commonly associated with diseases like strep throat. Bacilli are rod-shaped bacteria, and spirilla have a corkscrew shape. These differences are critical in microbiology for identification and understanding their pathogenic potential.