Saccharomyces

Class: Acromycetes

Order: Endomycetales

Family: Saccharomycetaeceae

Genus: Saccharomyces

Saccharomyces is saprophytic fungi (Yeast) found growing abundantly in sugary substance such as fruits, syrups, jams, nectar, honey, toddy etc. it is uni-cellular but sometimes the cell may remain attached giving the appearance of a pseudo mycelium. the cells are small oval or spherical in shape and grow as white or creamy colonies on the surface of solid nutrient media.

Each cell has a definite two layered cell wall made up of fungal cellulose with the chitin. The cell wall encloses the protoplasm which can be differentiated into outer ectoplasm and the inner endoplasm. The cell contains a large centroplasm consists of a single large nucleus, sub-cellular organelles like endoplasmic reticulum, ribosome, mitochondria, and reserved food material in the form of glycogen, volutin granules and oil globules.

REPRODUCTION

Saccharomyces reproduce by budding or fusion or by sexual reproduction.

BUDDING

It is the most common type of reproduction in which the parent cell gives rise to a small bud- like out growth. The nucleus of the parent cell divides in to two and one daughter nucleus along with cytoplasm enters the bud. The bud grows in size and may get a pinched-off from the mother cell or may remain attached to it intern forming bud, there by giving rise to pseudo mycelium.

SEXUAL REPRODUCTION
It is of isogamous type where two vegetative cells behave as gemates and put out small protuberances, which meats and forms conjugation tubes. The nuclei of the two gametes fuse along with cytoplasm and form a zygote which develops in to ascus. The diploid nucleus of the ascus under goes mitosis to form 4-8 ascospores which when release develop into new yeast cell.

Posted in: Microbiology