Role of the Pre-neck Appendage Protein (Dpo7) from Phage vB_SepiS-phiIPLA7 as an Anti-biofilm Agent in Staphylococcal Species

Abstract

Staphylococcus epidermidis and Staphylococcus aureus are important causative agents of hospital-acquired infections and bacteremia, likely due to their ability to form biofilms. The production of a dense exopolysaccharide (EPS) matrix enclosing the cells slows the penetration of antibiotic down, resulting in therapy failure. The EPS depolymerase (Dpo7) derived from bacteriophage vB_SepiS-phiIPLA7, was overexpressed in Escherichia coli and characterized. A dose dependent but time independent response was observed after treatment of staphylococcal 24 h-biofilms with Dpo7. Maximum removal (>90%) of biofilm-attached cells was obtained with 0.15 μM of Dpo7 in all polysaccharide producer strains but Dpo7 failed to eliminate polysaccharide-independent biofilm formed by S. aureus V329. Moreover, the pre-treatment of polystyrene surfaces with Dpo7 reduced the biofilm biomass by 53–85% in the 67% of the tested strains. This study supports the use of phage-encoded EPS depolymerases to prevent and disperse staphylococcal biofilms, thereby making bacteria more susceptible to the action of antimicrobials.

Bacteriophage-encoded virion-associated enzymes to overcome the carbohydrate barriers during the infection process

“…Pectate/pectin lyases are characterized by cleavage of the α-1,4 bonds of polygalacturonic acid. Enzymes possessing such domain have been described for Pseudomonas phages Φ15 and AF (Cornelissen et al 2011, 2012), Klebsiella phages (NTUH-K2044-K1–1, KP36) (Lin et al 2014; Majkowska-Skrobek et al 2016), Vibrio phage JA1 (Linnerborg et al 2001), and Staphylococcus phage vB_SepiS-ΦIPLA7 (Gutierrez et al 2015) (Table 1). Alginate lyases (mannuronate or guluronate lyases) characteristic for Pseudomonas and Azobacter phages (PT6) are able to degrade the α-1,4 bond of alginate, a linear polysaccharide of β-D-mannuronate, and its C5 epimer α-L-guluronate common for mucoid strains infecting cystic fibrosis patients (Davidson et al 1977; Wong et al 2000; Glonti et al 2010) (Table 1).…”

“…Depolymerases described and characterized to date are present in the phage virion within tail fibers or tailspikes on the baseplate, regardless of the phage family they originate from or the host bacterial species they infect (Table 1). One described exception is the depolymerase encoded by Staphylococcus phage vB_SepiS-ΦIPLA7, which shows 99% homology with a pre-neck appendage protein (Gutierrez et al 2015). Generally, depolymerases form elongated homotrimers that appear as protruding cell-puncturing devices on the virion, which aligns well with their biological function.…”

The Behavior of Staphylococcus aureus Dual-Species Biofilms Treated with Bacteriophage phiIPLA-RODI Depends on the Accompanying Microorganism

“…Moreover, numerous studies have already shown the ability of phages to remove biofilms formed by a variety of bacteria, including staphylococcal species (15)(16)(17)(18). Additionally, phage-encoded proteins, such as endolysins and exopolysaccharide depolymerases, can also be used for biofilm removal (19)(20)(21). Nevertheless, most studies available to date have focused on single-species communities, while only limited work has tackled the elimination of polymicrobial biofilms with phage-based products (22)(23)(24)(25)(26).…”

Advances and Future Prospects of Enzyme‐Based Biofilm Prevention Approaches in the Food Industry

“…Gutiérrez et al. () applied an exopolysaccharide depolymerase, Dpo7, to remove the biofilm formed by S. epidermidis and S. aureus in 24 hr. They found that the biofilms were removed by up to 27% to 85% in all exopolysaccharide‐producing bacteria, with the highest activity in S. epidermidis strain Z2LDC14.…”

“…Moreover, a number of phage-encoded proteins have been found to have polysaccharide depolymerase-like activities that act specifically on polysaccharide or polysaccharide-derived molecules. Gutiérrez et al (2015) applied an exopolysaccharide depolymerase, Dpo7, to remove the biofilm formed by S. epidermidis and S. aureus in 24 hr. They found that the biofilms were removed by up to 27% to 85% in all exopolysaccharide-producing bacteria, with the highest activity in S. epidermidis strain Z2LDC14.…”