Donnelly Holgersen (expertquilt0)

2 mg/ml), which were relatively stable in a certain pH or temperature range. A structure-activity relationship of the purified hemocyanin was determined based on the interaction of hemocyanin and different chromatographic medium, which revealed that the integrated hexamers played a remarkable role in its bacteriostatic activity. Moreover, the phenoloxidase activity of hemocyanin from Varuna litterata was found as the underlying cause of its antimicrobial potential.Glycinin basic peptide (GBP) is a natural antibacterial peptide. This study aimed to explore the antibacterial characteristics of GBP against Listeria monocytogenes (L. monocytogenes) by measuring the membrane potential, membrane permeability, cell damage, morphological changes, respiration metabolism inhibition and DNA content. GBP increased the surface zeta potential and decreased the trans-membrane potential of L. monocytogenes in a dose-dependent manner. Compared with the control, the electrical conductivities of GBP-treated bacterial suspensions were significantly increased. The percentages of bacteria with damaged membrane increased from 6.40% to 70.90% with GBP from 0 to 0.8 mg/mL. Obvious rupture and deform of bacterial cells with GBP were observed by transmission electron microscope (TEM), showing the destructive effect of GBP on L. monocytogenes. GBP also inhibited the embden-meyerhof-parnas pathway of the bacterial respiration metabolism and reduced the activities of its key regulator enzymes. Besides, the content of DNA in GBP-treated L. monocytogenes was lower than that in control.Diarrhea caused by Enterotoxigenic Escherichia coli (ETEC) causes high levels of morbidity and mortality in neonatal piglets. Owing to the abuse of antibiotics and emergence of drug resistance, antibiotics are no longer considered only beneficial, but also potentially harmful drugs. Supplements that can inhibit the growth of bacteria are expected to replace antibiotics. Tea polyphenols have numerous important biological functions, including antibacterial, antiviral, antioxidative, anti-inflammatory, and antihypertensive effects. We investigated the role of tea polyphenols in ETEC K88 infection using a mouse model. Pretreating with tea polyphenols attenuated the symptoms induced by ETEC K88. Furthermore, in a cell adherence assay, tea polyphenols inhibited ETEC K88 adherence to IPEC-J2 cells. When cells were infected with ETEC K88, mRNA and protein levels of claudin-1 were significantly decreased compared with those of control cells. However, when cells were pretreated with tea polyphenols, claudin-1 mRNA and protein levels were higher than those in cells without pretreatment upon cell infection with ETEC K88. TLR2 mRNA levels were also higher following cell infection with ETEC K88 when cells were pretreated with tea polyphenols. These data revealed that tea polyphenols could increase the barrier integrity of IPEC-J2 cells by upregulating expression of claudin-1 through activation of TLR2. Tea polyphenols had beneficial effects on epithelial barrier function. Therefore, tea polyphenols could be used as a novel strategy to control and treat pig infections caused by ETEC K88.Toxoplasma gondii differentiation from proliferating tachyzoites into latent bradyzoites is central to pathogenesis and transmission. Strong humoral immune response has been reported against tachyzoite antigens, however, antibody-mediated response towards bradyzoite antigens is poorly characterized. This work aimed to study the humoral immune response towards bradyzoite and associated cyst wall antigens particularly CST1. The immunoreactivity of 404 goats, 88 sheep and 92 human sera to recombinant (CST1 and SRS9) and native proteins of encysted bradyzoite along with well-established tachyzoite antigens (SAG1 and GRA7) was determined using ELISA, Western blot and immunofluorescence analysis (IFA). ELISA results revealed nearly 50% of sera contain T. gondii specific antibodies. Results were further validated u