There twenty nosocomial strains of methicillin-resistant Staphylococcus aureus (MRSA) were collected over Great Cairo during three months. Some facts were observed and recorded during that survey; the male infection percent (65%) was larger than of female (35%), the percent of infected blood cases was more than the others (45%) followed by diabetic foot (25%), vagina and pubic (10%), and sputum and buccal cavity (5%). On the other hand, marine soils were professionally collected from different coastal locations in Egypt. Forty marine actinomycete isolates were isolated and screened to produce β-lactamase inhibition activity. The screening test resulted in presence of only five isolates produced β-lactamase inhibition activity included a most potent one that symbolized Sm4. The latter was identified as Streptomyces tendae by using both classical and molecular techniques. The purification of β-lactamase inhibitory protein was carried out by using ion exchange and gel filtration column chromatographs, and then separated at 40 KDa by using SDS-PAGE. Simultaneously, purified β-lactamase inhibitory protein has produced antibacterial activity, so it has double inhibitory effect against MRSA strains. The β-lactamase inhibitory protein was found composed of 17 amino acids; however, therionine has a highest content (90 moles %) followed by arginine (75 moles %) and alanine (70 moles %).