Table 1.

Characteristics of the different bacteria included in our experiments with regard to the categories Gram staining [Gram-positive (+) or Gram-negative (−)], cell respiration (aerobic or anaerobic), pathogenicity (with typical disease if pathogenic) and localization (intra- or extracellular)

Bacterium	Abbr.	Gram staining	Cell respiration	Pathogenicity/disease pattern	Localization
Escherichia coli 0111:B4	HKEB	−	Facultative anaerobic	Non-pathogenic	Extracellular
Helicobacter pylori	HKHP	−	Micro-aerophilic	Pathogenic (peptic ulcers and gastritis)	Extracellular
Listeria monocytogenes	HKLM	+	Facultative anaerobic	Pathogenic (listeriosis)	Intracellular
Legionella pneumophila	HKLP	−	Aerobic	Pathogenic (legionellosis)	Intracellular
Lactobacillus rhamnosus	HKLR	+	Facultative anaerobic	Non-pathogenic	Extracellular
Mycoplasma fermentans	HKMF	No cell wall	Facultative anaerobic	Potentially pathogenic (arthritis)	Intra- and extracellular
Pseudomonas aeruginosa	HKPA	−	Aerobic	Pathogenic (pneumonia, osteomyelitis)	Extracellular
Porphyromonas gingivalis	HKPG	−	Anaerobic	Pathogenic (periodontal disease)	Extracellular
Staphylococcus aureus	HKSA	+	Facultative anaerobic	Normally non-pathogenic	Extracellular
Streptococcus pneumoniae	HKSP	+	Aerotolerant anaerobic	Pathogenic (pneumonia)	Extracellular