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A text search method has been developed with which errors within large data base compilations may be located if the citations contain redundant information. This study has been applied to the ASTM Infrared Spectral Indexof 91 875 spectra. Each citation within the data base contains some redundant information. If the citation is correct, the redundant information is the same; if the information differs, the citation is incorrect and an error has been located. The overall error was found to be between 3 and 5% within the limits of this study. The error search is general and can be applied to most chemical data base compilations.

Five pattern recognition methods are compared for their ability to classify binary infrared spectra. Included is a discussion of the time vs success balance for each of the techniques. Predictive ability decreases in the order maximum likelihood > distance > Tanimoto similarity ∼ Hamming distance > dot product. The time required for each prediction after the classifier has been developed increases in order maximum likelihood ∼ distance ∼ dot product < Tanimoto similarity ∼ Hamming distance.

Some form of information compression is essential if one is to be able to utilize effectively the increasingly large data compilations. One approach is to eliminate the intensity information, leaving spectra packed in a peak/no peak format. This paper reports the comparison of two simple discriminant functions for classifying binary infrared data. For the multicategory problem of 13 classes used in this investigation, random guessing would achieve about 8% correct classification. A dot product calculation produces 49.1% correct classification, while a distance measurement produces 58.7%. The results from this investigation are also qualitatively compared to previous work using infrared data which retained some intensity information. It is found that the binary packing of spectral data shows great promise in the area of infrared analysis.

A number of actinomycetes isolated from soil were found to produce one or more members of a new family of antibiotics, the cephamycins, which are structurally related to cephalosporin C. The cephamycins were produced in submerged fermentation in a wide variety of media by one or more of eight different species of Streptomyces, including a newly described species, S. lactamdurans. These antibiotics exhibit antibacterial activity against a broad spectrum of bacteria which includes many that are resistant to the cephalosporins and penicillins.

A number of actinomycetes isolated from soil were found to produce one or more members of a new family of antibiotics, the cephamycins, which are structurally related to cephalosporin C. The cephamycins were produced in submerged fermentation in a wide variety of media by one or more of eight different species of Streptomyces, including a newly described species, S. lactamdurans. These antibiotics exhibit antibacterial activity against a broad spectrum of bacteria which includes many that are resistant to the cephalosporins and penicillins.

Aside from penicillin, streptothricin is the only antibiotic whose pharmacologic properties indicate a suitability for general use in the animal organism.1, 2Interest in the development of an antituberculosis agent of microbiological origin led to in vitrotests of the efficacy of the only 2 antibiotics known which at present could possibly be of general use in animals or humans, namely, penicillin and streptothricin.Various species of mycobacteria were totally resistant to the action of penicillin, even as much as 1,000 Oxford units per ml. Further studies revealed that this resistance probably is due to the abundant formation of a penicillin-destroying enzyme, presumably penicillinase. Details of this are reported elsewhere.3A study of the inhibitory action of streptothricin for 5 Mycobacteriumcultures is included in Table I. Since streptothricin is stable, a single addition of the antibiotic was sufficient to maintain the desired unitage over the period of 6 to 8 weeks necessary for growth of some strains of mycobacteria. Streptothricin was particularly effective in Long's medium; this is probably the result of the alkalinity of the medium which is known to enhance the in vitroactivity of streptothricin.4The inhibitory range of 0.1 to 1.0 unit of streptothricin per ml places these Mycobacteriumcultures among the most sensitive organisms to streptothricin. M. phleipreviously was found sensitive.5A rough indication was obtained for the bactericidal action of streptothricin upon mycobacteria. Long's medium containing various quantities of streptothricin was inoculated heavily with 4 Mycobacteriumstrains. After 14 days' inhibition, portions of each culture were streaked on Long's agar to determine viability of the cells in the inoculum. Table II indicates that streptothricin was definitely bactericidal in low concentrations.