controling and kiling microbes

most resistant to least resistant

1-3-prions, endospores, mycobacteria, 4-6 cysts of protozoa, vegetative protozoa, gram negative bacteria, 7-10- fungi, viruses without envelopes, gram positive, viruses with envelopes. PEM (PEOPLE EAT MEAT) CVG ( CAN VICTOR GO) FVGV (FAT VIOLIN GOES VROOM)

Actions of Microbial Control Agents

Alter membrane permeability- make cells leaky. Damage proteins and nucleic acids- proteins are necessary for all functions in the cell.

exotoxins are

Are made of proteins All have a binding and active component Are most often made by gram positive bacteria Are never made by E.Coli Are part of the cell wall

antifungals do damage by

Injury to the plasma membrane- binds to or inhibits production of sterols Injury to the cell wall

why is pasturization used to treat food?

Most organism that causes disease or spoilage of food are destroyed by pasteurization.

A large hospital washes burn patients in a stainless steel tub. After each patient, the tub is cleaned with a quat. It was noticed that 14 of 20 burn patients acquired Pseudomonas infections after being bathed. Provide an explanation for this high rate of infection.

Quaternary ammonium compounds are most effective against gram-positive bacteria. Gram-negative bacteria that were stuck in cracks or around the drain of the tub would not have been washed away when the tub was cleaned. These gram-negative bacteria could survive the washing procedure. Some pseudomonads can grow on quats that have been accumulated.

Entamoeba histolytica and Giardia lamblia were isolated from the stool sample of a 45- year- old man, and Shigella sonnei was isolated from the stool sample of an 18- year- old woman. Both patients experienced diarrhea and severe abdominal cramps, and prior to onset of digestive symptoms both had been treated by the same chiropractor. The chiropractor had administered colonic irrigations (enemas) to these patients. The device used for this treatment was a gravity- dependent apparatus using 12 liters of tap water. There were no check valves to prevent backflow, so all parts of the apparatus could have become contaminated with feces during each colonic treatment. The chiropractor provided colonic treatment to four or five patients per day. Between patients, the adaptor piece that is inserted into the rectum was placed in a hot water sterilizer..what two mistakes were made by the chiro?

chriropracter did not sterilize the adapter correctly water should have been sterile water to r/u parasites

preserving food name two methods

desiccation - dry/ cant reproduce/ lox osmotic pressure-

toxins that harm humans are ony from bacteria

false

physical methods of control

heat filteration low temps high pressures

how to slow down the growth

heat, low temps,

physical method of control in lab..how do you kill microbes

heat, low temps, filter, high pressure

antivirals do:

prevents virus from entering the cell enzyme inhibator of reverse transciptase inhibitorse of protease interferons nucleoside analags

when microbes are in the form of _______they are incredibly hard to kill

prions

Which ones mean death to all the microbes?

sterilization

Why each of the following bacteria often resistant to disinfectants? a. Mycobacterium b. Pseudomonas c. Bacillus

a. All Mycobacterium species share a characteristic cell wall, thicker than in many other bacteria, which is hydrophobic, waxy, and rich in mycolic acids/mycolates. The cell wall makes a substantial contribution to the hardiness of this genus. b.Pseudomonas have the ability to metabolise a variety of diverse nutrients. Combined with the ability to form biofilms, they are thus able to able to survive in a variety of unexpected places. c .they have a structure call an endospore

name 4 factors that influence effectiveness of micro microbial treatemnts

Time of exposure Number of microbes Microbial characteristics Environmental influences-organic materials, more materials to get through it all

Sterilization- destruction of all forms of microbial life, including endospores Commericial sterilization- kills bacteria and the endospores of Clostridium botulinum Disinfection- destruction of the vegetative microbes Antiseptis-- destruction of the vegetative microbes on living tissue Sepsis- bacterial contaminationAsepsis- absence of significant contamination Sanitization-- lowers microbial counts Pasteurization-- kills organisms that cause spoilage- cide--means to kill (germicide, fungicide) -stat or -stasis-- means to stop (bacteriostasis)

Sterilization- destruction of all forms of microbial life, including endospores Commericial sterilization- kills bacteria and the endospores of Clostridium botulinum Disinfection- destruction of the vegetative microbes Antiseptis-- destruction of the vegetative microbes on living tissue Sepsis- bacterial contaminationAsepsis- absence of significant contamination Sanitization-- lowers microbial counts Pasteurization-- kills organisms that cause spoilage- cide--means to kill (germicide, fungicide) -stat or -stasis-- means to stop (bacteriostasis)