gram positive bacilli

• Bacillus was first discovered by Robert Koch
• Bacillus anthracis causes Anthrax
• clostridium and bacillus are organisms that are capable of producing Endospores
• endospores is a structure of survival and replication
• Endospores is created through aerobic manner meaning there must be presence of oxygen
• bacillus catalase : positive
• vigorous bubble formation is also known as Effervescence
• if added h2o2(hydrogen peroxide) to any species of bacillus it will be always positive reaction: it will be a positive reaction if there is a vigorous bubble formation.
• almost all species of genus bacillus is motile except: Bacillus anthracis as well as Bacillus mycoides
• Bacillus anthracis is also known as Anthrax bacillus if singular and Anthrax bacilli if plural
• Anthrax is an infection caused by bacteria from the genus Bacillus.
• virulence factors of bacillus anthracis:

  1. capsule
  2. exotoxin
• normal type of capsule that is produce by any organism is poly-sccharide capsule
• bacillus anthracis has distinct capsule which is called Poly-D-glutamic acid
• toxins

  1. can be metabolic by product
  2. can be degraded structure
• types of toxin according to its form:

  1. exotoxin
  2. endotoxin
• exotoxin of bacillus anthracis is protective exotoxin
• toxin that produce by a bacteria can also cause infection aside from bacteria
• exotoxin is commonly produce by gram positive bacteria
• some gram negative bacteria are also capable of producing an exotoxin
• most gram + bacteria produce exotoxin, howerver, some gram - bacteria can also produce exotoxin
• gram - bacteria can only produce endotoxin except for : Listeria monocytogenes
• listeria monocytogenes is the only gram + bacilli capable to produce endotoxin
• exotoxin are considered to be metabolic by-products and mostly made up of proteins
• endotoxin is degraded structure and mostly made up lipid
• lipopolysaccharide: a complex molecule containing lipid contents
• exotoxin has specific mode of action meaning there is target specificity.
• endotoxin is non-specific, there is non-targeted responce
• specific (target) in exotoxin:

  • brain/CNS - Neurotoxin
  • liver - hepatotoxin
  • kidney - nephrotoxin
  • wbc’s - leukotoxin
  • peripheral cells - histiotoxin
• non-specific ( non-targeted )

  -target all parts of our body.(general)

  common manifestations:

  • fever
  • shock
  • sepsis
  • DIC - disseminated intravascular coagulatio ( uncontrolled clot formation )
• exotoxin has low lethal dose while endotoxin has high lethal dose
• exotoxin is considered as immunologically complete
• endotoxin us immunologically incomplete
• exotoxin has a very high chance to produce anti-toxin or toxoids because of its immunologically complete structure
• endotoxin has a very low chance to produce anti-toxin because of its immunology incomplete.
• Protective Ag or protective exotoxin
• protective antigen is one of the exotoxins of bacillus anthracis
• 3 types of exotoxins of bacillus anthracis

  1. lethal factor
  2. edema factor
  3. protective antigen
• lethal factor causes cell death or necrosis, which is the death of a cell due to a toxin.
• edema factor causes edema