Aims Lectin is a nonimmunogenic glycoprotein that has been extracted mostly from the primary plant source leguminoase. Its ability to precisely recognize and bind to the complex cell bound structure enables it to play diverse roles. In this study, we obligate to define new sources of lectins since the production of lectins is very expensive. Therefore, we performed a study with the goal to isolate and characterize lectin from bacteria of plant origin and screen its ability as an antibacterial, antibiofilm and antiproliferative agent. Methods and Results We investigated isolates of environmental origin for their ability to produce lectin using phenotypic and molecular detection. The lectin was purified from an isolate AB119 which has abundant lectin activity and its molecular weight was determined by SDS-PAGE and HPLC. This lectin has a molecular weight of 30 kD and used to evaluate its antimicrobial, antibiofilm and antiproliferative activities using earlier published protocols. All bacterial isolates tested in this study showed the ability to produce biofilm which was inhibited in the presence of lectin significantly. In microtitre plate assay, the scale of biofilm inhibition by the purified lectin was significantly reduced for all bacterial species. Lectin inhibited the growth of all three tested bacterial species after treatment for 24 h and this antimicrobial effect was uniform to all species irrespective of Gram positive or Gram negative. The antiproliferative effects of lectin against HeLa cells were determined using MTT assay showed significant inhibitory effects on the proliferation at an IC50 of 10 μM for 24 h. Conclusion This study concludes that lectin has a promising application as an antimicrobial and, antibiofilm agent to control multidrug-resistant pathogen-associated infections. At the same time, it has also promising ability to control the proliferation of tumour cell as evident by our study results. Significance and Impact of Study AB119 lectin from A.baumannii species was verified for its capability to control microbial growth and its biofilm formation. Results showed lectin was able to reduce growth as well biofilm formation of both Gram-positive and Gram-negative bacterial species. Lectin has a promising application as an antibiofilm agent to combat the growing number of multidrug-resistant pathogen-associated infections.

The present study examined hospital-based serological tests of rickettsial infections and assessment for diagnosis of pyrexia of unknown origin (PUO). Blood samples were tested for Weil Felix antigens, ELISA for scrub typhus group and polymerase chain reaction (PCR) to detect the presence of DNA of spotted and scrub typhus group with the help of specific oligonucleotide. We tested 450 patient samples and found 101 Weil Felix-positive with 15 having ≥320 titres. IgM ELISA identified 32 (7.1%) positive cases. Positive PCR was seen in 13 (2.9%) samples, being only 40.1% of those testing positive for ELISA. Rickettsial infection is predominantly diagnosed through serological evidence in combination with molecular techniques. The Weil Felix test has a number of disadvantages and tends to provide false-positive results in a number of scenarios, especially where scrub typhus and spotted fever are widely distributed.