Improving of antibacterial activity for antibiotics by purified and characterized lectin from Acinetobacter baumannii

الملخص EN

Lectin has a wide range of applications in many fields as anti-tumor, anti-insect , antiviral and antifungal drug.

Here we reported lectin production from Acinetobacter as there is no report on lectin production from Acinetobacter.

In the present study a novel strain, Acinetobacter baumannii S3 isolated from sputum samples gave the highest production level of lectin by microscopic glass slide and microtiter plate methods and the hemagglutination activity was not blood-type specific.

Lectin was purified to homogeneity with a recovery yield of 72.72 % and 40.76 fold of purification by using ammonium sulfate at 35% saturation followed by QAE-Sephadex ion exchange chromatography and sephadex G-200 gel filtration chromatography.

The optimum activity of purified lectin was found at 30ºC and pH 7.

The best cofactors for lectin activity were Mn++ and Mg++ with relative activities of 132 and 122 %, respectively and severely inhibited in presence of Fe3+, Cu2+and detergents.

Lectin led to increase antimicrobial activity of antibiotics and had synergism effect, thus lectin may be useful adjuvant agent for the treatment of many bacterial infections in combination with antibiotics.