MCB 301 Exam 3 Study Guide with Complete Solutions

MCB 301 Exam 3 Study Guide with Complete Solutions endospore - Answer️️ -- a bacterial cell specialized for survival - incapable of cell division - form via differentiation - survival and dispersal mechanism for genetic material - resistant to environmental stresses - only 10-12% water - low metabolic activity - 10-15% calcium dipicolinate to stabilize spore coat molecules - has spore coat! 30-60% endospore formation - Answer️️ -- alternative to regular cell division - example of cell differentiation - form within the cytoplasm of bacteria - survival and dispersal mechanism for genetic material - maturation takes hours, then cell ruptures and releases it into the environment - expensive - only occurs when cell survival is threatened - highly regulated vegetative cells - Answer️️ -- cells of bacteria that do not differentiate TITLE: EMILLYCHARLOTTE 2024/2025 ACADEMIC PERIOD OWNER: EMILLYCHARLOTTE COPYRIGHT STATEMENT: ©2024 EMILLYCHARLOTTE. ALL RIGHTS RESERVED FIRST PUBLISHED: SEPTEMBER 2024 - capable of cell division - 70-80% water steps of sporulation - Answer️️ -1. DNA is replicated (same as in binary fission); nucleoid chills in the middle of the cell 2. cytoplasmic membrane invaginates to form spore septum 3. the cells are now unequal size 4. membrane of the larger cell grows around the smaller, mother engulfs the daughter cell 5. daughter cell is now surrounded by 2 membranes (forespore); original nucleoid is degraded. 6. special PG is synthesized between the two membranes, called the cortex. calcium dipicolinate is deposited to help protect DNA 7. spore coat proteins are deposited around cortex 8. outer forespore membrane is degraded 9. exosporium forms 10. mature spore is released as dormant and can stay that way for years until it finds the right environment Is the outer sporefore membrane found in the mature endospore? - Answer️️ -NOPE. just inner and cortex cortex - Answer️️ -- forms between inner and outer forespore membranes - made of special peptidoglycan TITLE: EMILLYCHARLOTTE 2024/2025 ACADEMIC PERIOD OWNER: EMILLYCHARLOTTE COPYRIGHT STATEMENT: ©2024 EMILLYCHARLOTTE. ALL RIGHTS RESERVED FIRST PUBLISHED: SEPTEMBER 2024 exosporium - Answer️️ -additional layer of endospore, outside spore coat layers of mature endospore - Answer️️ -inner forespore membrane, cortex, spore coat, exosporium germination - Answer️️ -...of spore. produces a vegetative cell once again things that can activate spores - Answer️️ -SUITABLE NUTRIENTS: - heat 60-65 degrees C for 10+ min - oxidizing or reducing agents - low pH - certain amino acids - nucleotides like adenine or inosine outgrowth - Answer️️ -- transitional step between germination and the vegetative cell - involves uptake of water, swelling, and breaking the spore coat - synthesis of macromolecules such as DNA, RNA, and proteins why doesn't spore coat dissolve in water? - Answer️️ -- made of hydrophobic amino acids with alipathic side chains that prevent water from entering the cell (ala, val, leu, ile, pro, phe, trp, met) - disulfide bonds of cysteine provide additional stability to the spore coat Are most endospore-forming bacteria G+ or G- ? - Answer️️ -G+ What is a typical shape for endospore-forming bacteria? - Answer️️ -rods. Bacillus and Clostridium are the most common genera TITLE: EMILLYCHARLOTTE 2024/2025 ACADEMIC PERIOD OWNER: EMILLYCHARLOTTE COPYRIGHT STATEMENT: ©2024 EMILLYCHARLOTTE. ALL RIGHTS RESERVED FIRST PUBLISHED: SEPTEMBER 2024 What is the typical metabolism for endospore-forming Bacillus? - Answer️️ -- obligate aerobes or facultative aerobes - most are chemoheterotrophs - ATP yield is theoretically 38 moles per glucose when oxygen is the terminal electron acceptor, but only 2 ATPs per glucose during fermentation - some species use homolactic fermentation, some use the butanediol pathway What is the typical metabolism for endospore-forming Clostridium? - Answer️️ -only capable of fermentation. most are obligate anaerobes; die in the presence of oxygen butanediol pathway - Answer️️ -- form of fermentation - 2 pyruvate react with a 3-enzyme system to form 2,3-buta