4.4.1 physical conditions of growth -> gaseous atmosphere

what is gaseous atmosphere?

some microbes require O2 for respiration to generate energy, some do not need at all and some can be killed in the presence of O2

what are the 3 enzymes that can detoxify the Reactive Oxygen Species?

superoxide dismutases

catalases

peroxidases

how does superoxide dimustases detoxify ROS?

neutralizes O2

how does catalases detoxify ROS?

break down H2O2 to water and O2

how does peroxidases detoxify ROS?

reduce H2O2 to water using NADH

what are the categories of microbes for gaseous atmosphere?

obligate aerobe

obligate anaerobe

facultative anaerobe

microaerophile

aerotolerant anaerobe

capnophile

what is the requirement for obligate aerobe?

requires O2 for respiration, cannot grow without O2

what is the requirement for obligate anaerobe?

do not require O2, cannot grow in the presence of O2

what is the requirement for facultative anaerobe?

do not require O2, can grow with out without O2 and if O2 is available can be used for respiration

what is the requirement for microaerophile?

requires O2, grows well at low levels, 2 - 10% but killed in atmospheric levels of O2

what is the requirement for aerotolerant anaerobe?

do not require O2, can tolerate O2

what is the requirement for capnophile?

grows bests at increased CO2 and reduced O2 levels