Bacterial toxins are the most important virulence factors that could hurt humans causing serious health problems. Staphylococcus aureus have a wide range of extracellular toxins; one of them is alpha toxin; haemolysin that degrade red blood cells. Thirty S. aureus isolates were isolated from clinical and animal-origin foods sample. S. aureus isolates were chosen for the phenotypic and genotypic detection of alpha toxin. Bacterial DNA was extracted and specific primers were designated for this study. PCR was depended to detect the prevalence of haemolysin-coding gene in local isolates in Iraq. On the other hand, silver nanoparticles (AgNps) were biosynthesized using food-origin bacterial isolate of Salmonella. The biosynthesis was done in optimized conditions, purified, and tested for their antimicrobial activity. Phenotypic detection methods revealed the ability of 70% to produce alpha toxin, whereas the genetic tool was very precise in detecting the genetic content (93.33%) of alpha toxin gene in clinical and animal-origin foods. The biosynthesized nanoparticles were with an average diameter of 44.89 nm. They have an antimicrobial activity against haemolysin-producing S. aureus isolates. Monitoring and understanding the haemolysin production by S. aureus strains in food samples can aid in implementing effective food safety measures to prevent contamination and ensure the safety of food products.

The increasing cases of bloodstream infections among children at neonatal intensive care units (NICUs) led this work to investigate biofilm production, antibiotics and the presence of ESβL genes in Serratia marcescens (S. marcescens) strains isolated from blood. Twenty S. marcescens strains were isolated and identified by the VITEK-2 system over 7 months from late 2022 to mid-2023 from Ibn Al-Balady Hospital in Baghdad. Kirby-Bauer test was used to measure antibiotic susceptibility. The results revealed that 95 L genes. The biofilm values increase with the accuracy of EsβL genes. Phylogenetic analyses based on the sequence of blaCTX-M and blaTEM were done with closely related genes in the GenBank using MEGA6 software. The distribution of blaTEM, blaCTX and blaSHV genes among local S. marcescens strains may be attributed to the indiscriminate use of antibiotics. The results confirmed the spread of ESβL genes in S. marcescens from blood infections among newborn infants.

BACKGROUND:Antibiotic resistance is a major problem threatening human beings. The genetic determinants that carry resistance genes can be transmitted in several ways in clinical and food environments. Hence, this research study aimed to investigate the presence of New Delhi metallo-beta-lactamase-1 (blaNDM-1) produced by enterotoxigenic Enterobacter cloacae in both clinical and food samples.METHODS AND RESULTS:Twenty-four isolates of Enterobacter spp. were isolated, seven isolates from food samples and 17 isolates from blood taken from neonates and children (1 day - 10 years old) resident in a children's hospital. Antibiotic susceptibility test to 14 antibiotics was performed for all isolates. Enterotoxigenicity of the clinical and foodborne isolates was detected phenotypically using Suckling mouse bioassay. Genomic deoxyribonucleic acid (DNA) was extracted from the isolated Enterobacter spp. that were detected resistant to imipenem. Polymerase chain reaction (PCR) was used to amplify blaNDM-1 gene followed by sequencing. The results of the bioassay revealed that 64.28% of E. cloacae ssp. cloacae isolates were enterotoxigenic. Two E. cloacae ssp. cloacae were imipenem resistant.CONCLUSIONS:This study showed that one isolate from a male child 1 < year was bla NDM-1 positive that was con-firmed by sequencing. This is the first report that revealed blaNDM-1 producing Enterobacter cloacae in Iraq.

Infectious diseases caused by infected tools in the environments are threaten to the safety and public health. Transmission sources of these infectious diseases are unknown, but it is thought that non-living materials called fomites, are the major source of acquired infections. Three hundred and one swabs were taken from different sources and cultured on blood agar to study heamolysis ability of isolated bacteria. In this study, MacConkey agar was used to isolate Gram-negative bacteria and Sabouraud agar (SDA) to isolate fungi. The biofilm formation test was done by Congo red plate assay. 41 (13.6%) bacterial isolates were obtained and (18.27%) of fungi were isolated on Sabouraud agar (SDA). Staphylococcus aureus was the more frequent bacterial species that isolated in this study. 29% of samples showed hemolysin activity on blood agar and 32%of the isolates were biofilm- producer. Results revealed that (7.9%) of Gram-negative bacteria harbored the fimH gene, (9%) harbored the icaA were Gram-positive and 6.3 % of fungal samples had HWP1 gene. Furthermore, (9.3%) from the total samples are bacterial samples harbored hla gene belong to Staphylococcus spp. Furthermore, (5.07%) of tested samples possessed hlyA gene were Gram-negative bacteria. We found in our study that infectious organisms can be transmitted from one individual to another by fomites responsible for acquired infection.

Lactic acid bacteria (LAB) have reported as antifungal, antibacterial, and immunostimulatory agents. Exopolysaccharide (EPS) of lactic acid bacteria effectively could stimulate the production of cytokines by macrophages. This study was aimed to extract, purified, and characterize the EPS from Leuconostoc mesenteroides subsp. Cremoris and to evaluate the immunostimulatory and antibacterial activities of EPS against extended-spectrum beta-lactamase (ESBL) producing Burkholderia cepacia strains. Nine EPSs producing L. mesenteroides subsp. cremoris strains were isolated from local dairy products and the isolated bacteria were identified by using API 50. Eight B. cepacia strains were isolated from different specimens in the hospitals of Medical city, Baghdad. Furthermore, genotypic and phenotypic detection of antibiotic resistance were determined including ESBL genes. EPS of L. mesenteroides subsp. Cremoris was extracted and purified by gel filtration chromatography. EPS physical and chemical analysis were performed to characterize it. Antibacterial and immunomodulatory effect of EPS were studied in vivo using mice and ELISA was used to determine the levels of IL-10 in the mice sera. The extracted EPS was found to have a maximum relative viscosity in water (3.51 dl/g) and maximum specific viscosity (2.93 dl/g), while the intrinsic viscosity recorded 1.41 dl/g. The chemical analysis of the extracted polysaccharide was found to contain the following components, carbohydrates, protein, uronic acids, hexosamines, acetyl groups, ketal linked pyruvate groups, phosphate groups, and sulfate groups, also show the following functional groups under infrared (IR) spectra (hydroxyl, alkanes, carbonyl, carbonyl of carboxylic acid, phosphates, and aliphatic amines). HPLC analysis revealed the presence of mannose as a major component with a calculated molecular weight of 1.71 × 103 g/mol. Genotypic detection of the blaPER-1 gene among ESBL producing B. cepacia strains showed the presence of blaPER-1 gene in three (42.86%) strains. Furthermore, to confirm the biological potential, the EPS was evaluated for its antibacterial activity against multidrug resistance B. cepacia strains in vitro and the result showed that the purified EPS was more effective than crude EPS in all concentrations. The protective activities of L. mesenteroides and EPS were observed when administered 7 days before and after B. cepacia infection, whereas therapeutic activities were monitored by administering EPS for 7 days after B. cepacia induction. This results revealed that the administration of L. mesenteroides and EPS significantly decreased the number of B. cepacia in liver, spleen, and lung (P < 0.05). Furthermore, they enhanced production of IL-10. In conclusion, the L. mesenteroides and its EPSs possess antibacterial and immunostimulator properties and are nontoxic with medicinal importance. Therefore, further studies in human participants should determin the role of L. mesenteroides and its EPS as an immunomodulatory and its relationship in the host protection to pathogens.