SUMMARY: A collection of 426 Haemophilus strains isolated from people with infectious diseases and from the normal flora of mucous membranes in humans and various animal species was studied in an attempt to revise and improve the taxonomy of the genus Haemophilus. The examinations included the determination of a number of biochemical and physiological properties, of which several had not previously been applied to the taxonomy of haemophili. The resulting data revealed many hitherto unrecognized characters of taxonomic significance, and several of the species can now be more accurately defined. The classification presented is supported by the DNA base composition of a large number of representative strains. A diagnostic key to the different taxa is presented. Haemophilus influenzae and H. parainfluenzae have been subdivided into a number of biotypes. It is possible to demonstrate a relationship between the individual biotypes of H. influenzae and the origin of the strains assigned to them. The results indicate that H. aegyptius, H. parahaemolyticus and H. paraphrohaemolyticus do not merit specific status. Four unnamed taxa of V-factor-dependent haemophili have been recognized. The name Haemophilus segnis is proposed for one of these taxa, which consists mainly of strains isolated from the human oral cavity. It is demonstrated that the name H. ducreyi has been used for different groups of bacteria, and that only one of these groups can legitimately be assigned to the genus Haemophilus. Haemolytic V-factor-dependent strains from swine, previously included in H. parahaemolyticus, are significantly different from strains of human origin and should be named H. pleuropneumoniae. None of the strains from swine and fowls were haemindependent. The relationships of these strains to the species H. suis and H. gallinarum, and to H. parasuis and H. paragallinarum are discussed. Haemophilus piscium is shown not to belong to the genus Haemophilus. The taxonomic position of H. aphrophilus is uncertain and its possible relationship to Actinobacillus actinomycetemcomitans requires further study. The positive correlation found between the ecology of the strains studied and their affiliation with the different taxa is discussed.

A Taxonomic Study of the Genus Haemophilus, with the Proposal of a New Species

This volume contains the edition of the International Code of Nomenclature of Prokaryotes that was presented in draft form and available for comment at the Plenary Session of the Fourteenth International Congress of Bacteriology and Applied Microbiology (BAM), Montreal, 2014, together with updated lists of conserved and rejected bacterial names and of Opinions issued by the Judicial Commission. As in the past it brings together those changes accepted, published and documented by the ICSP and the Judicial Commission since the last revision was published. Several new appendices have been added to this edition. Appendix 11 addresses the appropriate application of the Candidatus concept, Appendix 12 contains the history of the van Niel Prize, and Appendix 13 contains the summaries of Congresses.

International code of nomenclature of prokaryotes

Phylogenetic position of phytopathogens within the Enterobacteriaceae.

Summary: Serratia species, in particular Serratia marcescens, are significant human pathogens. S. marcescens has a long and interesting taxonomic, medical experimentation, military experimentation, and human clinical infection history. The organisms in this genus, particularly S. marcescens, were long thought to be nonpathogenic. Because S. marcescens was thought to be a nonpathogen and is usually red pigmented, the U.S. military conducted experiments that attempted to ascertain the spread of this organism released over large areas. In the process, members of both the public and the military were exposed to S. marcescens, and this was uncovered by the press in the 1970s, leading to U.S. congressional hearings. S. marcescens was found to be a certain human pathogen by the mid-1960s. S. marcescens and S. liquefaciens have been isolated as causative agents of numerous outbreaks and opportunistic infections, and the association of these organisms with point sources such as medical devices and various solutions given to hospitalized patients is striking. Serratia species appear to be common environmental organisms, and this helps to explain the large number of nosocomial infections due to these bacteria. Since many nosocomial infections are caused by multiply antibiotic-resistant strains of S. marcescens, this increases the danger to hospitalized patients, and hospital personnel should be vigilant in preventing nosocomial outbreaks due to this organism. S. marcescens, and probably other species in the genus, carries several antibiotic resistance determinants and is also capable of acquiring resistance genes. S. marcescens and S. liquefaciens are usually identified well in the clinical laboratory, but the other species are rare enough that laboratory technologists may not recognize them. 16S rRNA gene sequencing may enable better identification of some of the less common Serratia species.

Serratia Infections: from Military Experiments to Current Practice

In a study of the classification of members of the family Pasteurellaceae, the polyamine patterns of 101 strains were analyzed. These strains included the type strains of species belonging to the genera Actinobacillus, Haemophilus, and Pasteurella and additional strains of selected species, as well as numerous unnamed strains. Members of the genus Actinobacillus sensu stricto were characterized by the presence of 1,3-diaminopropane as the predominant compound. In the majority of the species of the genus Haemophilus sensu stricto 1,3-diaminopropane was also the major compound in the polyamine pattern. In contrast, Haemophilus intermedius subsp. gazogenes and Haemophilus parainfluenzae were characterized by high levels of 1,3-diaminopropane, cadaverine, and putrescine. These results confirmed the findings of Dewhirst et al. (F. E. Dewhirst, B. J. Paster, I. Olsen, and G. J. Fraser, Zentralbl. Bakteriol. Parasitenkd. Infektionskr. Hyg. Abt. 1 Orig. 279:35–44, 1993), who demonstrated that H. parainfluenzae is phylogenetically only distantly related to the type species of the genus Haemophilus, Haemophilus influenzae. The phylogenetic diversity of the genus Pasteurella sensu stricto determined by Dewhirst et al. was also reflected to some extent by different polyamine patterns. The common characteristics found in Pasteurella multocida, Pasteurella canis, Pasteurella dagmatis, Pasteurella stomatis, and Pasteurella sp. strain B were high levels of putrescine and spermidine and the presence of the unusual triamine sym-norspermidine. Pasteurella avium, Pasteurella gallinarum, and Pasteurella volantium contained high concentrations of 1,3-diaminopropane and spermidine. Pasteurella langaa contained only high concentrations of 1,3-diaminopropane, and Pasteurella anatis was characterized by the presence of 1,3-diaminopropane as the predominant compound and high levels of putrescine and spermidine. Our data demonstrate that polyamine patterns are useful for discrimination within the family Pasteurellaceae.

Discrimination of Members of the Family Pasteurellaceae Based on Polyamine Patterns

Serologic Patterns of Human Sera: Reciprocal Heteroagglutination Reactions of Human and Sheep Bloods.

The early years of the present century witnessed the publication of a great many papers, stimulated by the work and by the theories of Bordet and Metchnikoff, dealing with the production and mode of action of cytolytic and cytotoxic sera. To the cells of very diverse mammalian tissues specific antisera exhibiting lytic action, or activities so interpreted, were produced and upon the basis of inference many theories were developed concerning a variety of pathologic conditions. Experience has shown, however, that little of practical value has resulted from the demonstration of antibodies of this type, if the hemolysin, which is of such wide application as an indicator in serologic technic, be exduded. Until recently but little further attention has been paid to antibodies of this character, although from time to time attempts have been made to find in such serological methods a means for detecting malignancy. Freund and Kaminer, Lehmann-Facius, Neuberg, and Lumsden have all developed technics involving basically the cytolytic or cytotoxic principle. Some of these methods make use of native sera, others develop antisera by artificial immunization, but all are directed toward demonstrating an effect of the serum upon carcinoma cells or on a derivative of these cells. The renewed activity along these lines has been attended by an intensive search for possible specific antigenic components in cancer tissue, and, indeed, such have been found, with further proof that such antigens can serve for inducing specific reacting-bodies under experimental conditions. However, despite all demonstrations of this kind none of the serological reactions based upon earlier technical methods has proved to be even moderately satisfactory when applied to diagnostic ends. Thus it is that the reaction described by Lehmann-Facius, the so-called carcinolytic action, might seem to offer possibilities not only of development into a practical laboratory technic, but also for determining certain facts with regard to the relationship of carcinoma to diverse serological changes. Examination of the papers of Lehmann-Facius would suggest that from the technical standpoint the distinguishing feature of such tests

The Carcinolytic Action of Sera.

The following note records certain results of experiments, wholly unsuccessful, designed to duplicate and, it was hoped, to amplify the work reported by Roskin and his collaborators. During the period from 1929 to 1935 these authors published a series of sixteen papers dealing with the influence of irradiation upon the therapeutic efficiency of various medicinal agents. Eight of these papers detailed experiments showing that non-effective doses of salvarsan administered to mice infected with trypanosoma became effective if the mice were given appropriate treatment with ultra-violet light. It is also reported that the serum of normal mice, or of normal men, collected after a period of irradiation is able to exert the adjuvant effect upon the non-sterilizing dose of salvarsan. This active serum component, termed the \"A-factor,\" is described as being thermolabile and readily adsorbed to kaolin. It exhibits no specificity referable to host derivation, and is not elaborated by the irradiated animal subsequent to splenectomy or after blockade, either local or general, of the reticulo-endothelial system. It was this hypothetical \"A-factor\" which it was proposed to study in its relationship to other serological principles. An attempt was made to reproduce the system employed by Roskin, that is, mouse-trypanosome-salvarsan-light, to observe his cautions as to dosage with the trypanosome, the drug, and irradiation; but it must be pointed out that our strain of mice most certainly differed from his, our Trypanosomo equiperdum was not his equiperdum, our salvarsan may have been unlike his, and our source of ultra-violet light was not the same. In all of these respects, as well as in results, our experiments differed from his; consequently our tests cannot in any way be considered a refutation of his work. They simply mean that broad generalizations from the results with a particular set of reagents of this nature are not permissible.

The Hypothetical A-Factor and Trypanosome Infection.

The development of an immunity through processes other than those of a purely passive nature may be regarded as dependent upon three basic principles. First, there must be some agency or force to exert a stimulation; second, there must be a being-of complex antigenic pattern and serologic structure-to undergo the stimulation; and third, there must be response,-expressed as increased resistance, augmented antibody content, the establishment of an allergic state, or some combination of reactions of this character. Of these three basic factors, the first and the third have received abundant attention; the second has been largely neglected, despite the fact that common experience indicates that within the reacting tissues reside the elements which determine whether or not the response takes place at all, and if it occurs, whether it will be great or small. An increasing understanding of the importance of concurrence of antigenic materials is serving to explain many hitherto obscure phenomena. Nevertheless, the tendency prevails to regard the protoplasm of all individuals of a given species,-rabbits, for example,-as essentially the same, and when the inevitable differences in response to antigenic stimulation become apparent, to dismiss the matter as simply an expression of individual variability. But \"individual variability\" merely defines an observed condition; it explains nothing as to causes or mechanisms involved. It will doubtless be long before an explanation for such variability in serologic and immunologic reactions will be at hand; certainly it will not be available before more is known of the medium within which such reactions take place. The present report does not purport to answer any of these questions in any way; it is designed merely to record certain observed facts relative to three antibody elements that may be found in human sera. It is not suggested that any, or all, of these three antibodies bear any relationship whatever to immunity or to the capacity to

George H. Smith

Papers

Serologic Patterns of Human Sera: Reciprocal Heteroagglutination Reactions of Human and Sheep Bloods.

The Carcinolytic Action of Sera.

The Hypothetical A-Factor and Trypanosome Infection.

Serologic Patterns in Human Sera: Heteroagglutinins for Sheep, Mouse, and Hen Erythrocytes.