Abstract: The present invention discloses a lysin that is capable of killing Staphylococcus and the use thereof, belonging to the field of biological agents. The present invention discloses the amino acid sequence and the encoding gene sequence of the lysin. This lysin keeps active in a wide range of pH. It has lytic activity against Staphylococcus in pH 4-11. The recombinant protease constructed by the encoding gene can be solubly expressed in E. coli strain BL21 (DE3). The lysin can be used to effectively kill multiple species Staphylococcus in vitro, including methicillin sensitive Staphylococcus aureus (MSSA) and methicillin resistant Staphylococcus aureus (MRSA) isolated in clinics. This lysin can be used as an antibiotic for the treatment of staphylococcal infections in vivo. This lysin is also able to rapidly lyse staphylococcal cell wall; as a result, intracellular substances such as ATP and DNA are released. Those released substances can be used to detect the type of Staphylococcus.

Abstract: This invention discloses a lysin that can kill many species of Streptococci. A new lysin, ClyR, was constructed by the gene splicing method. The ClyR can effectively kill different species of Streptococci, including Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus suis, Streptococcus uberis, Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus mutans, Streptococcus equi, and various Enterococci and Staphylococcus aureus. ClyR shows good stability and is not sensitive to EDTA and high concentration of NaCl. Moreover, the ClyR is active in a wide range of pH and maintains high activity in pH 5-11. Recombinant protein ClyR is well expressed in E. coli stain BL21 (DE3). High doses of ClyR showed no apparent toxicity in mice. Furthermore, administration of 0.8 mg per mouse once is able to completely protect the mouse infected with lethal doses of Group B Streptococci.

Abstract: This invention discloses a lysin that can kill many species of Streptococci. A new lysin, ClyR, was constructed by the gene splicing method. The ClyR can effectively kill different species of Streptococci, including Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus suis, Streptococcus uberis, Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus mutans, Streptococcus equi, and various Enterococci and Staphylococcus aureus. ClyR shows good stability and is not sensitive to EDTA and high concentration of NaCl. Moreover, the ClyR is active in a wide range of pH and maintains high activity in pH 5-11. Recombinant protein ClyR is well expressed in E. coli stain BL21 (DE3). High doses of ClyR showed no apparent toxicity in mice. Furthermore, administration of 0.8 mg per mouse once is able to completely protect the mouse infected with lethal doses of Group B Streptococci.