Introduction of Microbiology

Microbiology

Scientific study of microorganisms, those being of

unicellular (single-celled), multicellular (consisting of

complex cells), or acellular (lacking cells)

Bacterium

Singular

Bacteria

Contains both DNA and RNA

Replication of DNA

2nd in Binary Fission

Zacharias Janssen

invented compounding of lens

Robert Hooke

described the forms of fungi such as bluish mold on a piece of leather

Antonie van Leeuwenhoek

first to observe and to experiment with microbes

Louis Pasteur

Discover the principle of immunization

Robert Koch

known for the isolation of microorganisms causing Anthrax and Tuberculosis.

Robert Koch

developed solid media for culturing bacteria and various techniques to isolate

bacteria

Joseph Lister

Father of Antisepsis developed antiseptic surgical procedures

Hans Christian Gram

developed the most important staining method

Alexander Fleming

discovered the antibiotic Penicillin

Edward Jenner

concept of vaccination was invented by this British physician

Lag Phase

Log Phase

Stationary Phase

Death or Decline Phase

Bacterial Growth Curve

Obligate aerobes

can grow only in the presence of oxygen

Aerobic

NEEDS OXYGEN

Facultative aerobes

are ordinary aerobes but can also grow without oxygen

Microaerophilic bacteria

bacteria that can grow in the presence of low oxygen and in the presence of low concentration of carbon dioxide

4%

percentage of low concentration carbon dioxide

Anaerobic Bacteria

can love without O2; lack superoxide dismutase and catalase hence oxygen is lethal to these organisms

Obligate anaerobes

bacteria that can grow only in the absence of oxygen

Aerotolerant anaerobes

use fermentation as process for producing energy rather than utilizing Oxygen

37C

optimum temperature for most of the pathogenic bacteria

Psychrophiles

cold loving microbes that grow within a temperature range of 0–20C

Mesophiles

These are moderate temperature loving microbes that grow between 25C and 40C Most of pathogenic bacteria belong to this group

pH 7.2 and 7.6

Most pathogenic bacteria grow between?

V. cholerae

example of the bacteria that can grow at an alkaline (8.2–8.9) pH

Phototrophs

bacteria deriving energy from sunlight

Chemoautotrophs

bacteria deriving energy from chemical sources

OSMOPHILIC BACTERIA

Organisms requiring high osmotic pressures

Shape, Gram Stain, Oxygen Demand

Classification of Bacteria

Aerobic, Anaerobic

Under oxygen demand

5–10% CO2, 15% O2.

They grow well in the presence of?

3%

In candle jar, how many percentage of CO2 can be achieved.

lactobacilli

can grow at acidic pH below 4.0

Stationary phase

plateau in number of living bacterial cells; rate of cell division and death roughly equal

Log phase

exponential increase in number of living bacterial cells

Death or decline phase

exponential decrease in number of living bacterial cells

Lag phase

no increase in number of living bacterial cells