Stuart Mudd

THE MITOCHONDRIA OF BACTERIA

Recent evidence from the biochemical, the genetic and the morphologic study of bacteria, in that chronological order, has indicated essential similarities of the bacterial cell to the cells of higher organisms. Recognition in bacteria of a large category of cytoplasmic granules as possessing characteristics which strongly suggest that they are the functional equivalents of the mitochondria of anirnaE and plant cells, has been a significant step. It is the purpose of this communication to summarize the properties of these cytoplasmic granules in bacteria, in so far as they have been worked out, and thus to arrive at a definition of the mitochondria of bacteria. Morphology. In electron micrographs under conditions in which the surround-

A cytological investigation of the mitochondria of three strains of Salmonella typhosa.

Various supravital mitochondrial indicators have been used on three strains of S. typhosa. Some variation in the pattern of staining was noted, which demonstrates the existence of a gradient of mitochondrial reactivities. The mitochondria were differentiated from nuclei and cell wall, and Showed no structural relationship to terminal flagellar spheres.

Factors conditioning the Accumulation and Disappearance of Metaphosphate in Cells of Corynebacterium diphtheriae.

Abstract The deposition of metaphosphate in the form of metachromatic granules in resting cells of Corynebacterium diphtheriae occurred in the presence of various oxidizable tricarboxylic acid cycle compounds. The addition of K + and orthophosphate greatly enhanced this deposition. Glucose, either alone or with K + and orthophosphate did not lead to the formation of these metachromatic granules. Metachromatic cells in the presence of glucose, citrate, and formate, as well as in the endogenous control, eventually lost their metachromasy after 16 hr. incubation in the absence of external P. In the presence of fumarate and malate there occurred a constant increase in metachromasy; after 16 hr. the index of metachromasy was doubled. Distribution studies of the phosphorus components of the metachromatic cells, before and after incubation in glucose and malate, indicate that in the presence of glucose, RNA P increased at the expense of the metaphosphate. In the presence of sodium malate, metaphosphate increased at the expense of the RNA P.

Epidemiology and treatment of chronic staphylococcal infections in the household.

The epidemiological cycles of chronic staphylococcal infections in households are discussed and ther various methods of control that have been used are examined. The authors conclude there is no sovereign remedy and suggest a number of possibilities for research.

The detection of susceptibility to whooping cough: II. Clinical standardization of the diagnostic skin test reagent and its use in institutional and in private practice

Summary The agglutinogen of phase I H. pertussis prepared by a method of chemicalextraction has been compared with the sonic-extracted material which has been shown to be a satisfactory skin test agent for susceptibility to pertussis. The acid-extracted agglutinogen was standardized against the sonic product and found to be more potent, and to give more clear-cut reactions. Review of these data showed that a twenty-four-hour reading time could berecommended. At present the skin test dose is estimated in units by laboratory methods, and assayed finally by human intradermal inoculation. This agglutinogen gives identical results to those obtained with the sonic-extracted material; there is no reaction even in large doses in normal (susceptible) individuals, and an allergic reaction at the site of injection in any individual with solid immunity to whooping cough from either immunization or previous attack of the disease. In an institution with annual outbreaks of whooping cough, the use of agglutinogen before the anticipated epidemic was followed by a significant decrease in the number of cases, all of which occurred in the group predicted by the skin test to be susceptible. Yearly skin testing of new students followed by immunization of all susceptible children has resulted thus far in the absence of whooping cough from this school. Comparison of the agglutinogen skin test with the Strean toxin test in childrenfrom City of Philadelphia Health Centers has been made. The results clearly indicated a close correlation between the history and the agglutinogen skin test results. On the other hand, results from the use of the Strean test revealed that satisfactory correlation between history and toxin test only existed in the group of known susceptible children. The use of agglutinogen has a definite place as a public health measure in periodic examinations of young children. The duration of primary immunization may be determined while the antigenicity of agglutinogen produces a prompt recall of any existing antibacterial immunity.

The Susceptibility to Furacin of Bacterial Strains IResistant to Sulfonamides or Antibiotics.

Summary and Conclusions Several Gramnegative and Gram-positive organisms resistant to sulfonamides, streptomycin and penicillin and the parent susceptible strains were tested in parallel for their susceptibility to furacin. No differences were observed be-t tween the resistant and susceptible strains in I regard to their susceptibility to furacin. Re-e sistance to penicillin, streptomycin or sul-5 fathiazole does not result in any change to furacin resistance.

PURIFICATION AND PROPERTIES OF THE PROTEIN OF THE “M SUBSTANCE” OF GROUP A HEMOLYTIC STREPTOCOCCUS

The M substance characterizes each of the various types of virulent Group A hemolytic streptococci, as is shown by specific precipitation of extracts of the hl substance with appropriate antisera.l The typing obtained by the use of the M substance agreed with that previously obtained for the same strains by protection tests. More recent studies2 also have identified the M substance with the substance in intact streptococci which stimulates the production of protective antibodies in animals. The active material isolated from the neutralized N/20 HCl extracts used for typing of the streptococci has been designated the M substance by Lan~efield,~ who also showed that its reactivity with antisera is rapidly destroyed by proteolytic enzymes. Although the type-specific substance thus was shown to be a protein, it did not give rise to antibodies when injected into rabbits. Stamp and Hendry4 modified the isolation procedure, principally by using a milder extraction temperature, and obtained a fraction which induced active immunity in mice. Heidelberger and Kendall,5 by extracting ground streptococci with increasingly alkaline solutions, isolated a fraction which produced type-specific precipitins when injected into rabbits. Their preparations contained phosphorus. Mudd and collaborators have used sonic treatment of the streptococci and neutral extraction to obtain a fraction with typespecific properties. In a recent paper6 summarizing these studies i t was concluded that two serologically active components were present and that the predominant component was a nucleoprotein of broad reactivity and the other was a type-specific material probably related to the M substance or the T substance recently described by Lancefield.’ In the studies of Hirst and Lancefield2 a substance was isolated by a modification of the original mcthod of Lancefield which induced active immunity in mice and which in rabbits gave rise to precipitins and to protective antibodies passively transferable to mice. Considerable nucleic acid was present in their preparations in addition to protein. At the same time studies done in our laboratory* had shown that about a third of the material extracted a t 56” C. with N/20 HCl was nucleic

Aspects of Bacteria as Cells and as Organisms Part I

Publisher Summary Bacteria, which are among the most numerous members of the microbiologic population, are at the same time microscopic plant cells and individual organisms. Because of the practical importance of bacteria in medicine, agriculture, and industry, bacteriology is cultivated mainly as an applied science. This chapter discusses the aspects of bacteria as cells and as organisms. The observations of genetic behavior in bacteria include the phenomena of the continuity of genetic determiners, their recombination and segregation, which are currently expressed in the idioms of classical genetics. Analysis of nuclear phenomena in bacteria by the most revealing techniques presently available is exhibiting the sequences of classical mitosis. Bacterial cells conform the familiar pattern of cellular organization, in which they possess external cell wall, cytoplasmic membrane, and protoplast containing well-differentiated nucleus and organelles for organized energy exchange or mitochondria. The fundamental biochemical similarities between the cells of bacteria and of higher plants and animals are also discussed.

DELAYED‐TYPE HYPERSENSITIVITY TO S. AUREUS AND ITS USES

Staphylococcus aureus, as a gram-positive, pyogenic, opportunist invader, has been under investigation for a very long time. The senior author of this paper spent years at the Rockefeller Institute during the classic investigations of the pneumococci under Cole, Avery, and Heidelberger, and of Streptococcus pyogenes under Dochez, Lancefield, and their collaborators. It is not surprising, therefore, that the team with which he is associated began intensive study of Staphylococcus aureus with the almost unconscious presupposition that the dynamics of infection and immunity revealed in these earlier studies would in general be found in the golden coccus. Some ten years of investigation, however, have shown quite clearly that S. aureus is a “Ding am selbst.”

REDUCING SITES IN PACTERIAL CELLS OF THE ANAEROBIC GENUS CLOSTRIDIUM AND THEIR DIFFERENTIATION FROM OTHER CELL STRUCTURES

Granular sites of oxidation-reduction are readily demonstrable in the cells of bacteria of the genus Clostridium, using either intravital redox indicators or phospholipid stains. These granules in Clostridium do not give the reactions for cytochrome oxidase. In other respects their tinetorial reactions and distribution resemble those of the oxidation-reduction sites of other bacteria, which have been defined as bacterial mitochondria (2). The reducing granules are differentiated from cell-walls and intracellular septa, nuclei, iogen granules and spores. During the process of sporulation reducing granules are demonstrable within the cytoplasm of the spore bearing cell, and in particular adjacent to the outer border of the spore. With maturation of the spore and disappearance of most or all the cytoplasm of the mother-cell, reducing granules could no longer be demonstrated.