Premium
Summer meeting 2013 – when the sleepers wake: the germination of spores of B acillus species
Author(s) -
Setlow P.
Publication year - 2013
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/jam.12343
Subject(s) - spore , germination , spore germination , biology , peptidoglycan , bacterial spore , bacillus (shape) , endospore , microbiology and biotechnology , botany , cell wall
Summary Spores of B acillus species can remain dormant and resistant for years, but can rapidly ‘come back to life’ in germination triggered by agents, such as specific nutrients, and non‐nutrients, such as C a DPA , dodecylamine and hydrostatic pressure. Major events in germination include release of spore core monovalent cations and C a DPA , hydrolysis of the spore cortex peptidoglycan ( PG ) and expansion of the spore core. This leads to a well‐hydrated spore protoplast in which metabolism and macromolecular synthesis begin. Proteins essential for germination include the G er P proteins that facilitate germinant access to spores' inner layers, germinant receptors ( GR s) that recognize and respond to nutrient germinants, G er D important in rapid GR ‐dependent germination, S po VA proteins important in C a DPA release and cortex‐lytic enzymes that degrade cortex PG . Rates of germination of individuals in spore populations are heterogeneous, and methods have been developed recently to simultaneously analyse the germination of multiple individual spores. Spore germination heterogeneity is due primarily to large variations in GR levels among individual spores, with spores that germinate extremely slowly and termed superdormant having very low GR levels. These and other aspects of spore germination will be discussed in this review, and major unanswered questions will also be discussed.