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In this review, I will describe honeybee biology from my prospective as a veterinary pharmacologist and will provide a summary of my research project to search for effective drugs to control American foulbrood, a bacterial disease of honeybees. In conclusion, mirosamicin, a macrolide antibiotic, as a preventive and glutaral, an alkylating agent, as a disinfectant were the most promising drugs.

Whether or not resistance to macrolide-lincosamide-streptogramin type B antibiotics (MLS) can be induced by many macrolide antibiotics (Mac), was inquired in Bacillus licheniformis EMR. Resistance to MLS in the strain was induced by erythromycin, oleandomycin, clarithromycin, roxithromycin, narbomycin, picromycin, kujimycin A or B, mycinamicin I, or rosamicin. On the contrary, josamycin, spiramycin, tylosin, rokitamycin, midecamycin, and miokamycin as well as lincosamide and streptogramin type B antibiotics could not induce MLS-resistance. The results suggest that two common chemical residues of the inducer Mac, that is, 1) a single monosaccharide at C5 in the 14- and 16-membered lactone rings, and 2) one polar group such as dimethylamino or methoxyl at C3' in the sugar, are likely to be responsible for showing the activity of MLS-resistance inducer in Bacillus licheniformis EMR.

Ozone resistance of spores of 2 strains of Bacillus isolated from laboratory animals was examined. Each of 0.02 ml of phosphate-buffered saline at pH 7.0 containing 10(6) Bacillus spores was dropped onto sterilized filter strips, wood chip bedding, pellets of diet, cloth pieces and stainless steel plates. After drying at room temperature, the test materials were exposed to ozone gas of different concentrations at 90% RH. Exposure to 200ppm ozone for 6 hours was sufficient to kill spores in filter strips, but a little higher concentration or a little longer period of ozone fumigation was necessary for sterilization of wood chips, cotton cloth pieces and steel plates. The present results indicated that 600ppm ozone fumigation for 6 hours might be effective for routine sterilization of cages, wood bedding, working clothes and other materials used in laboratory animal facilities. However, exposure to ozone gas of 500 or 1,000 ppm for 6 hours or 200 ppm for 24 hours could not kill spores in pellets of diet, suggesting that dietary protein inhibited the bactericidal activity of ozone.

The MICs of Aztreonam (AZT) against 590 clinical isolates of Gram-negative bacilli were determined. About 13.4% (79 strains) of the isolates were AZT-resistant (MIC; 12.5 micrograms/ml less than or equal to). The resistance pattern against various beta-lactams and the effects on MICs of combination of Clavulanic acid (CVA) and AZT against AZT resistant strains suggested that AZT was inactivated by either type of IV (K1), Va (OXA1), or PSE2 beta-lactamases.