PMID:26621799

Citation	Guo, T, Xin, Y, Zhang, C, Ouyang, X and Kong, J (2016) The potential of the endolysin Lysdb from Lactobacillus delbrueckii phage for combating Staphylococcus aureus during cheese manufacture from raw milk. Appl. Microbiol. Biotechnol. 100:3545-54
Abstract	Phage endolysins have received increased attention in recent times as potential antibacterial agents and the biopreservatives in food production processes. Staphylococcus aureus is one of the most common pathogens in bacterial food poisoning outbreaks. In this study, the endolysin Lysdb, one of the two-component cell lysis cassette of Lactobacillus delbrueckii phage phiLdb, was shown to possess a muramidase domain and catalytic sites with homology to Chalaropsis-type lysozymes. Peptidoglycan hydrolytic bond specificity determination revealed that Lysdb was able to cleave the 6-O-acetylated peptidoglycans present in the cell walls of S. aureus. Turbidity reduction assays demonstrated that Lysdb could effectively lyse the S. aureus live cells under acidic and mesothermal conditions. To further evaluate the ability of Lysdb as a potential antibacterial agent against S. aureus in cheese manufacture, Lactobacillus casei BL23 was engineered to constitutively deliver active Lysdb to challenge S. aureus in lab-scale cheese making from raw milk. Compared with the raw milk, the viable counts of S. aureus were reduced by 10(5)-fold in the cheese inoculated with the engineered L. casei strain during the fermentation process, and the pathogenic bacterial numbers remained at a low level (10(4) CFU/g) after 6 weeks of ripening at 10 °C. Taken together, all results indicated that the Lysdb has the function as an effective tool for combating S. aureus during cheese manufacture from raw milk.
Links	PubMed Online version:10.1007/s00253-015-7185-x
Keywords	Animals; Bacteriophages/enzymology; Bacteriophages/genetics; Cattle; Cheese/microbiology; Endopeptidases/genetics; Endopeptidases/metabolism; Endopeptidases/pharmacology; Fermentation; Food Contamination/analysis; Food Contamination/prevention & control; Food Handling; Lactobacillus delbrueckii/genetics; Lactobacillus delbrueckii/virology; Milk/microbiology; Staphylococcus aureus/drug effects; Staphylococcus aureus/physiology; Viral Proteins/genetics; Viral Proteins/metabolism; Viral Proteins/pharmacology
edit table

Annotations

Gene product	Qualifier	GO Term	Evidence Code	with/from	Aspect	Extension	Notes	Status
9CAUD:U3PJ04		GO:0006553: lysine metabolic process	ECO:0000314:		P		Figure 2. showcases the lytic activity of Phage LysdB against Streptococcus Aureus strains. Shows that LysdB is effective in eliciting a lytic response in Streptococcus Aureus and is a great deterrent of its growth. The figure also shows that lytic activity is temperature and pH dependent. Figure 5. shows that Lysdb was able to significantly decrease S. Aureus numbers in raw milk model and further proves its effectiveness as an antibacterial agent.	complete CACAO 12675

References

See Help:References for how to manage references in GONUTS.