18.2 Endospore-Forming Firmicutes产芽胞的厚壁菌 Key genera:Bacillus,Clostridium,Sporosarcina, Heliobacterium Distinguished on the basis of cell morphology,and the shape and cellular position of endospore Generally found in soils - Endospores are advantageous for soil microorganisms (a) (b) (c)
Chen Feng, Microbiology, SJTU 18.2 Endospore-Forming Firmicutes 产芽胞的厚壁菌 • Key genera: Bacillus, Clostridium, Sporosarcina, Heliobacterium – Distinguished on the basis of cell morphology, and the shape and cellular position of endospore – Generally found in soils – Endospores are advantageous for soil microorganisms
18.2 Endospore-Forming Firmicutes Bacillus and Paenibacillus芽胞杆菌和类芽孢杆菌属 Many produce extracellular hydrolytic enzymes that break down polymers产胞外水解酶类 -Many bacilli produce antibiotics可产抗生素 Bacillus thuringiensis produce insect larvicides 云金芽胞杆菌可产伴胞晶体 Endospore Crystal 2012 Pearson Educston,ine
Chen Feng, Microbiology, SJTU • Bacillus and Paenibacillus 芽胞杆菌和类芽孢杆菌属 – Many produce extracellular hydrolytic enzymes that break down polymers 产胞外水解酶类 – Many bacilli produce antibiotics 可产抗生素 – Bacillus thuringiensis produce insect larvicides 苏 云金芽胞杆菌可产伴胞晶体 18.2 Endospore-Forming Firmicutes
18.2 Endospore-Forming Firmicutes Clostridium梭菌属 -Lack a respiratory chain,anaerobic厌氧 Mainly found in anaerobic pockets in the soil Also live in mammalian intestinal tract - Some are pathogenic;others cause diseases such as botulism,tetanus,and gangrene可l起肉 毒杆菌中毒、破伤风和坏疽 (a) (b) (c)
Chen Feng, Microbiology, SJTU • Clostridium 梭菌属 – Lack a respiratory chain, anaerobic 厌氧 – Mainly found in anaerobic pockets in the soil • Also live in mammalian intestinal tract – Some are pathogenic; others cause diseases such as botulism, tetanus, and gangrene 可引起肉 毒杆菌中毒、破伤风和坏疽 18.2 Endospore-Forming Firmicutes
18.2 Endospore-Forming Firmicutes Sporosarcina芽胞/八叠球菌 Unique among endospore formers because cells are cocci instead of rods -Strictly aerobic,spherical cells严格好氧 Common in soils 8 snelo ele!c
Chen Feng, Microbiology, SJTU • Sporosarcina 芽胞八叠球菌 – Unique among endospore formers because cells are cocci instead of rods – Strictly aerobic, spherical cells 严格好氧 – Common in soils 18.2 Endospore-Forming Firmicutes
18.2 Endospore-Forming Firmicutes Heliobacteria 螺旋杆菌 Phototrophic gram-positive bacteria Anoxygenic phototrophs and produce a unique pigment bacteriochlorophyll g - Strict anaerobes Reside in soils and also in highly alkaline environments (e.g.,soda lakes and alkaline soils) Have nitrogen-fixing capabilities -6 Contains four genera: ·Heliobaterium.螺旋杆菌属 。Heliophilum (a) pue uebipeWL ·Heliorestis (c) ·Heliobacillus.螺旋菌属 ue6ipeW'L'W CA(b)
Chen Feng, Microbiology, SJTU • Heliobacteria 螺旋杆菌 – Phototrophic gram-positive bacteria – Anoxygenic phototrophs and produce a unique pigment bacteriochlorophyll g – Strict anaerobes – Reside in soils and also in highly alkaline environments (e.g., soda lakes and alkaline soils) – Have nitrogen-fixing capabilities – Contains four genera: • Heliobaterium螺旋杆菌属 • Heliophilum • Heliorestis • Heliobacillus螺旋菌属 18.2 Endospore-Forming Firmicutes