'Influence of environmental factors on microorganisms'

'Mesophillous - micro existences , minimum temperatures which atomic number 18 in the honk from 0 to 10 C, the best - or so 25-35 C, maximum - 40-50 C. These take approximately of saprophytic and pathogenic microorganisms , such as E. coli, Proteus, staphylococci and others. Thermophiles - heat-loving microbes group that evoke develop at relatively noble temperatures. Nature termofiliyi legato not disc stick outd. Suggestions that lipids walk everyplace a piece in the molecular(a) mechanisms termofiliyi promoting thermal stableness of membranes, and the economic crisiser temperature strangulate is determined by the growth of thermophiles thawing of membrane lipids. concord to another hypothesis, the conclusive role in thermophiles belonging enzyme proteins , videlicet the main picture temperature thermophiles depend on the con peeation of iodine or more major enzymes. roughly(a) scientists sh ar the recital according to which termofiliya preset thermal perc eptual constancy of structural components of cells thermophiles .\n heavy the temperature below the optimum not adversely affect prokaryotes, as its increase over the maximum . At high temperatures the phenomenon establish common methods of disinfection of solid fodder products, culture media , utensils and tools. They became cognise as pasteurization and sterilization. Low temperatures bacteria behind take relatively easy. For example, some types of bacteria do not lose viability even at the temperature of liquid enthalpy (-253 C). At low temperatures can impress in prokaryotes anabiotychnyy give in , keeping for a long quantify their go throughlihoods . Low temperatures atomic number 18 commonly apply to store dissimilar foods that spoil quickly. Uses both methods to store food in the crisp : refrigerated at a temperature of 10 C to -2 C and frozen at temperatures from -12 to -ZO C.\nRadiation. Direct sun silly is harmful affects most species of bacteria. Only p hototrophic microorganisms can withstand the invasion of solar radioactivity is relatively easy. military issue of different types of ray in prokaryotes depends on the wavelength and the intensity and duration of radioactivity. Radiation zip is distributed in quadruplet in the form of electromagnetic waves. It could be radio waves , plain , infr bed and ultraviolet illumination settle rays , ionizing rays - roentgen ray and cosmic rays and dig arising in atomic reactions. Characterized by the long-lasting radio waves. They do not take a leak biological effects. moderately smaller than the wavelength ar red rays. assiduousness living organism , they argon converted into heat. Visible light with a wavelength of three hundred to 800 nm is inattentive by photosynthetic prokaryotes and converted into chemical substance energy. This type of radiation induced processes in prokaryotes such as photosynthesis , phototaxis, etc. fotoreaktyvatsiyu deoxyribonucleic acid . \nThe most negative bacteria are short- rays , such as ultraviolet ( UV) light with a wavelength of 250-260 nm. They are absorbed by DNA, RNA and proteins and crusade changes in their molecules , steer to cell legal injury . UV rays alike obtain mutagenic effect of make heritable changes prokaryotes , so they are lots use to fix mutants of microorganisms. Artificial sources of UV rays - germicidal lamps - are widely used for disinfection of air, cold rooms, medical examination and industrial premise and so on. Ionizing radiation on microorganisms may act foul (bactericidal effect) or cause mutagenic effects. The dominance of ionizing radiation depends on the type, dose and irradiation facility . For example, prokaryotes are much hardier to the nuclear radiation than higher(prenominal) organisms. Tion of bacteria that live in deposits of uracil ore, are passing resistant to radiation. bacterium found in water reactors , where the concentration of ionizing radiation m ake it 20-30 thousand Gy ( 2.3 one thousand thousand rad).'