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We have synthesized a series of 3-substituted succinimides and their in vitro antibacterial activities have been tested towards Gram-positive and Gram-negative bacteria from the ATCC collection. Some of them possess significant antibacterial activity against Gram-positive organisms (Staphylococcus aureus ATCC 25923 and Enterococcus faecalis ATCC 29212) but all are poorly active or inactive against Gram-negative organisms (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853). The compounds with the lowest minimal inhibitory concentrations (esters of 3-hydroxy succinimides) are also the most cytotoxic against green monkey Vero cell line (ATCC CCL-81) and could explain that perhaps apoptosis should be implicated in eukaryotic cell cytotoxicity of succinimides.

In the field of our research programs concerning novel antimicrobial agents, a series of N-substituted imides was synthesized. These compounds were obtained by cyclization of amido-acids in acetic anhydride/sodium acetate or hexamethyldisilazane/zinc bromide for the hydroxy-aromatic derivatives. The hydroxy-alkyl maleimides were directly prepared by condensation of the corresponding amino-alcohol with maleic anhydride in boiling toluene. Most of N-substituted maleimides showed an interesting antimicrobial activity towards bacteria from the ATCC collection (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853) but the MIC values for P. aeruginosa were always high (128 microg/ml). The imides with alkyl substituents showed higher activities than aromatic analogues with MIC values in the range of 8-32 microg/ml. Comparatively, succinimides were practically inactive.

The present report describes a simple and rapid dot-immunobinding assay combined with a chemiluminescence detection system for screening hybridoma supernatants for specific monoclonal antibodies (MAbs). Small rectangular nitrocellulose filters dotted with either crude mixtures of antigens, or with control samples, were placed in six well plates, incubated with hybridoma supernatants, then stained with peroxidase-conjugated anti-mouse IgG. The reaction was performed with a chemiluminescence detection system. We used this method to screen hybridoma supernatants for MAbs against a 354 amino acid polypeptide of hog cholera virus (HCV) gp33-gp55 protein expressed as a fusion protein. We also extended it for the screening of MAbs against foot-and-mouth disease virus (FMDV). The chemiluminescence dot-immunobinding assay (CDIA) was compared with neutralization (N) and immunofluorescence (IF) screening tests and some FMDV seroneutralizing MAbs were found to be either poorly reactive or undetected by the IF test. The advantage of the present method is that it detects in only one step all MAbs detected in the IF and/or N tests together with some MAbs not detected by either of these methods. The present method is at least 356 times more sensitive than the IF test.