Table 2 Comparison of the properties of antibiotic, phage, and endolysin as antibacterial therapeutic agents

Bacteriocidal specificity

Broad spectrum more common than narrow spectrum

Typically narrow, species or strain specificity

Relatively broad lytic activity

[82, 83]

Proliferation

Non-proliferation

Self-proliferation

Non-proliferation

[11, 84]

Mode of action

Applied from without, target specific sites, typically disrupts one bacterial process

Applied from without, disrupt many essential cellular processes

Applied from without, target bonds in the peptidoglycan

[83, 85]

Bacteriocidal speed

Short time between administration and eradication of bacteria

Long time between administration and eradication of bacteria

Rapid bacterial activity within seconds of contact

[14, 86]

Intracellular activity

Diffusion through membranes allows for treatment of intracellular bacteria

Unable to penetrate eukaryotic cells

Few or modified ones (e.g., CPP-fused endolysins) can enhance intracellular efficacy

[77, 86, 87]

Resistance development

Prone to develop resistance

Resistance occurs quite frequently

No resistance has ever been reported over number of treated generations

[88, 89]

Antibiofilm activity

Not very effective against biofilms

Effective antibiofilm agents with limited penetration

Relatively effective antibiofilm agents with higher destruction of biofilms

[13, 83]

Immune response

Generally non-immunogenic

Interaction with immune systems and susceptible to clearance by antibodies

Immunogenic, lower degree of antibody neutralization

[26, 51, 90]

Pharmacokinetics

Establish the relationship between concentration and the magnitude of killing activity

Little clinical evidence that defines optimal dosages and pharmacokinetic parameters of therapy

Defined concentration at site of infection and in blood circulation

[29, 88, 89]