Environmental Influences and Control of Microbial Growth

University:
Northwest College
Course:
MOLB-2210 | General Microbiology
Academic year:

2023
Views:

312

Pages:

4
Author:

Carissa Thomas

Microbiology Environmental Influences and Control of Microbial Growth Microbial Nutrition A process by which chemical substances (nutrients) are acquired from the environment and used by microbes in cellular activities Essie Microbial Nutrition Essential nutrients – must be provided to an organism Two categories of essential nutrients: Macronutrients – Store required in large quantities; play principal roles in cell structure and metabolism so • Proteins, carbohydrates Micronutrients or trace elements – at e required in small amounts; involved in enzyme function and maintenance of protein structure • Manganese, zinc, nickel Sunlight supplies the basic source of energy on Earth for most organisms. Photo synthesizers can use it directly to produce organic nutrients that feed other organisms. Non-photosynthetic organisms extract the energy from chemical reactions to power cell processes. Gases: the atmosphere is a reservoir for nitrogen, oxygen, and carbon dioxide essential to living processes. CO2 Plant litter Soil microbes Nutrients Soil community Organic compounds Aquatic microbes °C K 50 320 40 30 310 300 20 290 280 270 10 0 -10 -20 -30 -40 260 250 240 230 © Kathy Park Talaro Nutrients are constantly being formed by decomposition and synthesis and released into the environment. Many inorganic nutrients originate from nonliving environments such as the air, water, and bedrock. Complex communities of microbes exist in nearly every place on earth. Microbes residing in these communities must associate physically and share the habitat, often establishing biofilms and other interrelationships. pH 0 1 Acidic 2 3 4 [H+] Acid 5 6 7 8 Neutral 9 10 11 12 13 14 The temperature of habitats varies to a significant extent among all places on Earth, and microbes exist at most points along this wide temperature scale. Basic (alkaline) [OH–] Base The acid or base content (pH) can show extreme variations from habitat to habitat. Microbes are the most adaptable organisms with regard to pH. © Courtesy: Pacific Northwest National Laboratory