Figure 1: Top view of biofilm development over time: The right panel is magnified to highlight the structures observed at 72 h. The population dynamics of a B. subtilis biofilm as a function of time were determined by harvesting samples from biofilms expressing reporters at 12, 24, 48, and 72 h of development [6].

Figure 2: Colony morphology of B. subtilis strain 3610 wild type (left image) and its matrix mutant (Cells after 3-d of growth on 1.5% agar MSgg medium); and effect of the antimicrobial nisin (0.6µM) on B. subtilis biofilm morphology (right image). Cells closer to the disk containing nisin are more wrinkled due to the presence of more matrix-producing cells [10].

Figure 3: Stage process for development of a biofilm (Lennox 2011)

Human Disease
Biofilm-forming Bacteria
Cystic fibrosis pneumonia
P. aeruginosa and Burkholderia cepacia
Pseudomonas pseudomallei
Necrotizing fasciitis
Group A streptococci
Musculoskeletal infections
Staphylococci and other Gram-positive cocci
Otitis media
Haemophilus influenzae (Non-typable strains)
Biliary tract infection
E. coli and other enteric bacteria
Urinary catheter cystitis
E. coli and other Gram-negative rods
Bacterial prostatitis
E. coli and other Gram-negative bacteria
Gram negative anaerobic oral bacteria
Dental caries
Streptococcus spp. and other acidogenic Gram positive cocci

Table 1: Some human disease associated with bacteria biofilms

Food-borne pathogens
Growing surface
Listeria monocytogenes
Dairy processing plant, conveyor belt
Pseudomonas spp.
Drain, vegetable and meat surface
Bacillus spp.
Pepelie, joint in processing environment, hot fluid
Salmonella spp.
Poultry processing environment

Table 2: Food-borne pathogens and spoilage bacteria in biofilm

Medical Devices
Causative organism
*Urinary catheter, Intra-urine device, Prosthetic heart valve, Central venous catheter
Coagulase-negative Staphylococci
*Urinary catheter, Central venous catheter
Klebsiella pneumoniae
*Artificial hip prosthesis, Central venous catheter, Intra-urine device
Pseudomonas aeruginosa
*Artificial voice prosthesis, Central venous catheter, Intra-urine device
Candida albicans
*Artificial hip prosthesis, Central venous catheter, Intra-urine device, Prosthetic heart valve
Staphylococcus aureus
*Artificial hip prosthesis, Prosthetic heart valve, Urinary catheter
Enterococcus spp.

Table 3: Microorganisms associated with biofilm on indwelling medical devices