上游充通大学 Shanghai Jiao Tong University 4.11.2 Chemical properties of endospore Calcium-dipicolinic acid complex-10%dry weight 有钙-吡啶二羧酸复合物，占干重的10%； Small acid-soluble spore proteins(SASPs) ·Protection of DNA o Energy and carbon source during germination ·小酸溶性孢子蛋白(SASP),有助于保护DNA,且在 萌发时提供能量和碳源。 Shanghai Jiao Tong University
Shanghai Jiao Tong University Shanghai Jiao Tong University 4.11.2 Chemical properties of endospore Calcium-dipicolinic acid complex-10% dry weight含 有钙-吡啶二羧酸复合物，占干重的10%； Small acid-soluble spore proteins (SASPs) • Protection of DNA • Energy and carbon source during germination • 小酸溶性孢子蛋白（SASP），有助于保护DNA，且在 萌发时提供能量和碳源
Dipicolinic acid(DPA)and calcium associate with the carboxyl groups to form a tough complex吡啶二羧酸与钙离子通过羧基形成复合物。 (a)Structure of DPA Ca+O0CN COO-+Ca+-OOCN COO+Ca+> (b) Carboxylic acid groups (b)How Cat cross-links DPA molecules to form a complex
Dipicolinic acid (DPA) and calcium associate with the carboxyl groups to form a tough complex吡啶二羧酸与钙离子通过羧基形成复合物。 (b) How Ca+ cross-links DPA molecules to form a complex. Structure of DPA
4.11.3 Spore formation Vegetative cell During endospore formation,a vegetative cell Developing spore is converted to a nongrowing,heat-resistant structure. Sporulating cell In B.subtilis,the entire sporulation process takes Mature spore ●t Petan Locaon about 8 hours. As many as 200 genes are involved in the sporulation process
4.11.3 Spore formation During endospore formation, a vegetative cell is converted to a nongrowing, heat-resistant structure. In B.subtilis, the entire sporulation process takes about 8 hours. As many as 200 genes are involved in the sporulation process
Figure 3.33 Vegetative cell Developing spore edd!H sueH Sporulating cell edd!H sueH Mature spore 2012 Pearson Education,Inc
Figure 3.33 Vegetative cell Developing spore Sporulating cell Mature spore © 2012 Pearson Education, Inc
Detail:In stages 0 to ll, Vegetative cell Wall Stage 0 Cytoplasmic membrane DNA DNA becomes more dense DNA浓缩 Stage I Stage ll ④足8⊙ Cytoplasmic membrane invaginates to form spore septum 细胞膜内陷而形成孢子隔膜 是
Detail: In stages 0 to II, DNA浓缩 细胞膜内陷而形成孢子隔膜