General Microbiology

Measurement of Bacterial of Growth A convenient method is to determine turbidity by photoelectric colorimeter or spectrophotometer.  The cell number can be counted as total cell number as well as viable count. Viable Count Viable number of bacteria can be counted by inoculating the suspension onto solid growth medium and counting the number of colonies. Since each colony is the end product of one viable bacterium, their count gives the number of viable bact…

Classification: Neutrophiles (pH = 7.0) - P. aeruginosaqo - Clostridium sporogenes - Proteus species Acidophiles (pH < 7.0) - Thiobacillus thiooxidans - Sulfollobus acidocaldaarius - Bacillus acidocaldarius Alkaliphiles (pH > 7.0) - Nitrobacter species - Streptococcus pneumoniae…

The cell cycle 1) Labile cells (GI tract, blood cells) - Described as parenchymal cells that are normally found in the G0 phase that can be stimulated to enter the G1 - Undergo continuous replication, and the interval between two consecutive mitoses is designated as the cell cycle - After division, the cells enter a gap phase (G1), in which they pursue their own specialized activities •    If they continue in the cycle, after passing the r…

NUTRITION OF BACTERIA Nutrients Chemoheterotrophs: nutrient source is organic material Bacteria also requires a source of  minerals. Oxygen On this basis bacteria have been divided into four groups. Obligate Anaerobes: These grow only under conditions of high reducing intensity. These bacteria catalase peroxidase, superoxide dismutase and cytochrome systems Clostridium and Bacteroides are important examples. Facultalive Anaerobes. These can …

COMPLEMENT The complement system primarily serves to fight bacterial infections.  The complement system can be activated by at least three separate pathways.  1) alternative pathway - - The alternative pathway of complement activation starts with the spontaneous hydroysis of an internal thioester bond in the plasma complement component C3 to result in C3(H2O). - The smaller cleavage products C3a, C4a, C5a, sometimes called "anaphylatoxins&q…