sarcina

Sarcina is a genus of bacteria known for producing distinctive cubical packets of cells. The name derives from the Latin sarcina, meaning a small bundle or cluster, reflecting the characteristic arrangement observed under the microscope.

Microbiologically, Sarcina species are Gram-positive, nonmotile, and typically anaerobic or microaerophilic. A hallmark feature is the way the cells divide in two perpendicular planes, forming cubical packets that resemble a lattice or cube of cells. They are generally slow-growing and can be difficult to culture in standard laboratory conditions.

Ecology and distribution vary by species. Sarcina has been detected in environmental samples such as soil and plant matter, and one species in particular—Sarcina ventriculi—has been recovered from the human stomach and from gastric contents in animals. In humans, S. ventriculi is rarely pathogenic, but it has been associated with gastric disturbances, especially in individuals with delayed gastric emptying. Reported clinical associations include emphysematous gastritis and gastric ulcers, though a direct causal relationship remains unproven and cases are uncommon.

Taxonomy and history: The genus has a long-standing textual association with Gram-positive cocci that form packet-like arrangements. Modern classifications have refined its placement within related groups, but the cubical cell arrangement continues to be a defining microscopic characteristic used in identification.

Significance: In clinical and diagnostic microbiology, recognition of the distinctive cubical multicellular arrangement aids identification of Sarcina, though infections are rare and the organism is not a common cause of disease.