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X-Ray diffraction, infrared spectra and density of murein, the rigid component of almost all bacterial cell walls, were measured using gram-negative (Spirillum serpens) and gram-positive (Lactobacillus plantarum) strains. X-Ray diffraction of dried foils of murein showed Debye-Scherrer rings, indicating periodicities of 0.93 to 1.00 and 0.44 nm. The comparison of the infrared spectra of chitin and murein showed that their amide I and amide II bands have the same frequencies. With isopycnic density gradient centrifugation of murein a density of ... = 1.46 g × cm-3 was observed. Based on these data, on theoretical considerations and on model building the following structure of murein is proposed: the structure of the glycan chains in murein is similar to that of chitin and cellulose. The peptides consisting of alternating D- and L-amino acids have the 2.27 helical conformation. They are linked to the carbohydrate chains through their N-terminus and form two hydrogen bonds with the sugar residues. This linkage causes an angle of about 150° between the carbohydrate and peptide chains. [ABSTRACT FROM AUTHOR]

The microbial flora of palms and the interdigital space between the thumb and forefinger was determined in nurses and in a control group. Significant differences in the incidence of Streptococcus viridans, Bacillus sp., Micrococci and a heterogeneous group of biochemically inactive gram-negative organisms were observed between the nurses and controls. Twenty-four per cent of both nurses and control subjects were found to be carriers of coagulase-positive, staphylococcus. The bacterial flora of the interdigital space resembled that of the palm. [ABSTRACT FROM AUTHOR]

The spectrum of illness and the immunologic response produced by cholera in volunteers were studied. The strains of Vibrio cholerae used were classical Inaba 569B and classical Ogawa 395. An oral dose of 108 organisms in buffered saline was required to induce the diarrhea of cholera. When given with live organisms, NaHCO3 lowered the infecting dose from 108 to 104 organisms. Clinical manifestations of infection varied from culturally positive formed stools to “rice water” diarrhea. Severe diarrhea did not have an explosive onset but rather progressively increased in volume during a 24-hr period. In 45 % of cases the stool was positive for V. cholerae before the onset of diarrhea. Titers of vibriocidal antibody rose after diarrhea, peaked the second week after challenge, and rapidly fell during the next four weeks. [ABSTRACT FROM PUBLISHER]

Bacterial lipopolysaccharide endotoxins (LPS) obtained by phenol-water extraction from oral strains Bacteriodes melaninogenicus and Fusobacterium were studied in the electron microscope. The LPS particles had a characteristic morphology comparable to that of LPS from other Gram-negative microorganisms. The LPS appeared as circular structures or discs delimited by single or trilaminar membranes, or as short rods composed of two electron-dense membranes separated by a fine, less-dense layer. Teeth with adhering soft and calcified bacterial plaque, which were extracted because of advanced periodontal disease, were obtained and processed for electron microscopy. Close examination of thin sections revealed an abundance of particles in the dental plaque which closely resembled those found in LPS preparations of GRAM-negative oral microorganisms. Circular as well as rod-like particles were identified. These particles, which were most frequent in regions containing Gram-negative bacteria, were distinctly different from the granular, filamentous, and other structures previously reported in the intercellular matrix of the dental plaque. It was concluded that the circular and rod-like structures described represent free bacterial lipopolysaccharide. LPS particles were found superficially in the plaque as well as in deeper layers and in regions undergoing calcification. In regions containing Gram-negative bacteria, intercellular mineral deposition often occurred in close association with the LPS particles. [ABSTRACT FROM AUTHOR]

Increased titres of heterophile antibodies to rat erythrocytes occurred in twelve of twenty-seven patients after renal transplantation. In seven of these twelve patients the titre rise appeared to be associated with rejection. Heterophile antibody formation showed no consistent kinetic pattern after transplantation and no definite relationship between rise in antibody titre and rejection can be claimed. Patients with very high heterophile antibody titres were however prone to rejection. Heterophile antibodies to rat erythrocytes cross-reacted with human and monkey kidney cells and a subpopulation of these antibodies also with human B erythrocytes. The antibodies were not of the Forssman or Paul-Bunnel-type and their appearance could not be related to ABO or HL-A incompatibility. The heterophile antibodies, primarily of IgM class, are suggested to be produced in response to B-substance related antigens in Gram-negative bacteria and non-HLA isoantigens. Approximately 35% of transplantation sera or sera from patients with kidney disease had IgG antibodies reacting with human and monkey kidney cells, human thyroid cells and A and B erythrocytes. Anti-kidney IgG antibodies in certain sera cross-reacted with rat erythrocytes. One-third of the patients with renal disorders had increased heterophile antibody titres. [ABSTRACT FROM AUTHOR]

Neutrophils from three patients with recurrent infections were studied for defects in the phagocytic process. In one, random and directed migration, adherence and ability to kill Gram-negative bacteria were defective. In a second patient random and directed migration was abnormal, but adherence was unimpaired; this patient also had an impaired ability to kill Gram-negative bacteria. The third patient had defective leucocyte motility, inability to reduce nitro-blue tetrazolium dye, and deficient killing of both Staphylococcus aureus and Gram-negative organisms. This patient's mother showed an intermediate bacterial killing defect consistent with the heterozygous state. The previously unrecognized patterns of defects in these patients emphasize the importance of early cell-membrane associated events to the ultimate success of the bactericidal process, and illustrate the heterogeneity of defects responsible for impaired neutrophil function. [ABSTRACT FROM AUTHOR]

The ability of fatty acids to sensitize gram-negative and ram-positive bacterial cells to the action of bacteriolytic enzymes was studied. By synergetic effects between bacteriolytic enzymes and fatty acids. isolated from Myxococcus such bacterial, which were otherwise resistant to the enzymes, could be lysed. Isobranched and unbranched acids with 11-15 carbon atoms were active and could sensitize Bacillus megaterium and Aerobacter aerogenes to the action of bacteriolytic enzymes from myxobacteria and to lysozyme. The sensitizing activity of tetradecanoic acid was enhanced with increasing concentration even after the solution was saturated. Neither ethylene diaminetetraacetate (0.1 and 1 mM) nor Triton X-100 (1 ‰) could sensitize resistant bacteria to the action of bacteriolytic enzymes. However, they were active in combination and they could also increase the effect of tetradecanoic acid. [ABSTRACT FROM AUTHOR]

Two pea (Pisum sativum L. ) cultivars and a kidney bean (Phaseolus vulgaris L.) cultivars were grown in water cultures at differently diurnal temperature (15,20, 24, 30°C) or at 10°C night temperature combined with various day temperatures (20, 24, 27,33 or 35°C) in the root medium. The inoculated plants were more sensitive to the extreme temperature than the plants supplied with combined nitrogen (KNO3). The middle-European pea cv. Violetta was adapted to somewhat higher root temperature than the northern one cv. Torsdag II, the latter showing better growth at lower temperatures, when the plants were inoculated with the same Finnish Rhizobium strain (HA1). Espesically at optimum day temperature the nitrogen fixation and consequently the dry weights of the inoculated plants were greatly increased when the night temperature was lowered. The optimum temperature for the growth of free-living Rhizobium strains (HA1 and H43) for peas was found to be 25 ° C and that of a strain (P103) for some what higher. Effective nitrogen fixation by nodulated legunes without a supply of combined nitrogen is achieved only what the optimum temperature range for root function is very close to the optimum for the rhizobia. [ABSTRACT FROM AUTHOR]

The role of immunoconglutinin (IK) in phagocytosis was investigated using an in vitro opsonic test system. Phagocytosis of Gram-negative bacteria was increased when pre-treated with rabbit serum containing immunoconglutinin. The enhanced phagocytosis was reflected by an increase in the number of macrophages engaged in phagocytosis as well as an increase in the opsonic index. Heat inactivation of the sera completely destroyed this opsonic activity. The data indicate that immunoconglutinin potentiates the opsonic activity of serum by increasing the amount of complement fixed to the bacteria. IK may also influence the rate of pliagocytosis by providing immune aggregates of suitable size, thus facilitating ingestion of immune complexes. [ABSTRACT FROM AUTHOR]

The action of antibodies and of the haemolytic complement system does not induce immune immobilization of Treponema pallidum, but only destroys superficial wall structures of these Gram-negative organisms. In sensitized and complement coated treponemes the immobilization is a result of the lysozyme interaction with the mucopeptide layer of the cell wall. In a lysozyme-free medium, immunologically damaged treponemes are able to repair the defects in the outer layers of their cell wall structures. Furthermore, it is shown that the long lag period in immune immobilization of T. pallidum can only partly be explained by the interaction of lysozyme with the treponemes. [ABSTRACT FROM AUTHOR]

The killing and lysis of Escherichia coli by human serum have been measured simultaneously at frequent intervals for periods of 30–60 minutes. The kinetic effects of varying the amounts of lysozyme, antibacterial antibody and complement have been studied. The rate of lysis is largely controlled by the lysozyme concentration but complement is also necessary. Killing is closely related to complement concentration. Antibody is needed in such small amounts that it is rarely a limiting factor. Inhibition of serum lysozyme by anti-human lysozyme prevents lysis and reduces killing but both are restored to normal by addition of egg-white lysozyme. Both lysis and killing are stopped by bentonite absorption of serum and complete return to normal is not attained by subsequent addition of egg-white lysozyme. In a lysozyme-free system lysis does occur after some delay probably due to the action of complement and antibody alone. In the presence of adequate complement and antibody the loss of complement (measured haemolytically) in bentonite treated serum is inadequate to account for the fall in bactericidal activity. A new bentonite absorbable factor (BAF) essential for complete serum bactericidal power is postulated. [ABSTRACT FROM AUTHOR]

The bactericidal capacity of the fixed macrophages of foetal and neonatal rats and chicks was investigated. It has been shown that as a population the phagocytic cells of these embryos lack a bactericidal mechanism for certain strains of Gram-negative bacteria, even in the presence of specific antibody. Neonates, however, were shown to have developed such a mechanism soon after birth. The implication of these findings is discussed in relation to antibody formation. [ABSTRACT FROM AUTHOR]

Urinary excretion of diazotizable amines in acute febrile disease was demonstrated 90 years ago. These substances were subsequently identified as metabolites of trytophan via the kynurenine pathway and the hepatic enzyme tryptophan pyrrolase (TP) was established as a regulator of this pathway. Animal studies have previously shown that TP has a circadian periodicity of activity and can be induced by gram-negative infections in the intact animal. Steroid administration also can enhance TP activity whereas endotoxin inhibits TP. This study measured urinary excretion of kynurenic acid (KA) and xanthurenic acid (XA), two tryptophan metabolites via the kynurenine pathway, in 26 hospitalized children with a variety of febrile disorders and 10 age-matched control subjects. Increased excretion of these metabolites was noted in the febrile patients and was unrelated to etiology of the fever. Circadian periodicity in the excretion of these metabolites was observed in both normal and febrile individuals. Significant group periodicity was not note for minimal and maximal excretory values did not occur synchronously in patients within any group. Two patients with endotoxic shock failed to exhibit an increased excretion of kynuremic acid and xanthurenic acid presumably because of inhibition of TP. A biochemical basis for the therapeutic use of exogenous corticosteroids in endotoxic shock is postulated. [ABSTRACT FROM AUTHOR]

Deals with a study which conducted in vitro tube sensitivity tests for strains of Hemophilus (H.) influenzae. Evaluation of the effectiveness of some antimicrobials against H. influenzae; Test of the antibiotic, Cephaloridine; Patterns of sensitivity.

The so-called simple proteins isolated from the endotoxin of Serratia marcescens 08 and whole cells Escherichia coli 0 141:K85(B) by aqueous phenol treatment were characterized by the determination of hydrodynamic properties, electrophoretic behavior, immunochemical specificity and chemical analysis. The chemical composition of both proteins revealed the presence of small amount of lipid A constituents such as glucosamine, phosphorus and fatty acids; the β-hydroxymyristic acid regarded as the characteristic marker for lipid A was present in all protein preparations. Since the treatment of intact endotoxin or bacterial cells with aqueous phenol results in the formation of two fragments (a lipopolysaccharide and a lipid A-protein), both of which are characterized by the presence of lipid A constituents, this dissociation seems to be caused by cleavage of a phenolsensitive linkage within the molecule of lipid A rather than at its point of attachment to the protein moiety. Thus, the "simple" protein preparations consist of the protein moiety and a small segment of lipid A. Contrary to previous views, such protein preparations are not simple proteins if this designation implies absence of constituents other than amino acids. However, for a historical reason we suggest that the term simple protein be retained for protein fragments isolated by aqueous phenol treatment of intact endotoxins. The simple protein from Serratia marcescens 08 was treated successively with trypsin and pronase. The resulting trypsin and pronase cores contained increasing amounts of lipid A constituents firmly bound to the residual protein moiety. Since lipid A was separated as an entity from the prorty in moiety only after acid hydrolysis of the pronase core, it is proposed that in intact endotoxin lipid A is covalently linked to the protein moiety. The absence of any detectable glucosamine and fatty acids m the mixture of peptides and amino acids released by trypsin and pronase, indicated a single point attachment between the lipid A and protein moieties. The protein moieties from Serratia marcescens and Escherichia coli were immunogenic and possessed a common antigenic determinant. Both trypsin and pronase cores retained the immunogenicity and revealed the presence of a common antigen with the parent simple protein. This second set of antigenic determinant(s) different from the specific O-antigens seems to be located in the protein moiety close to lipid A. [ABSTRACT FROM AUTHOR]

A measure of evolutionary divergence between three species of the enterobacteriaceae was made by studying the physical properties of a protein common to all three, N-(5'-phosphoribosyl)-anthranilic acid isomerace indole-3-glycerol phosphate synthetase, a bifunctional enzyme of the tryptophan biosynthetic pathway. The protein was purified to near homogeneity from Aerobacter aerogenes, Escherichia coli, and Salmonella typhimurium. The purified proteins were found to be very similar in their ultraviolet absorption spectra, fluorescence emission and excitation spectra, and molecular weights. Various determinations of the molecular weights varied from 4.4 to 5.1 x 104 Daltons, and no significant differences were observed between the purified proteins and the enzymes in crude extracts. The electrophoretic behaviour of each of the three purified proteins on polyacrylamide gels with sodium dodecyl sulphate were similar and consistent with each enzyme consisting of a single polypeptide chain. Peptide patterns of each of the proteis were obtained following digestion with trypsin plus chymotrypsin. Close homology in primary structure between the proteins was suggested by the observation that approximately half the peptides of any proteins were identical. Comparison with similar data from a previous study on the α subunit of tryptophan synthetase suggests that there has been no great difference in the rate of divergence of the α subunit and phosphoribosyl-anthranilate isomerase-indole-glycerol-phosphate synthetase in the species studied. [ABSTRACT FROM AUTHOR]

Carnitine dehydrogenase from Pseudomonas aeruginosa A7244 catalyzes the oxidation of carnitine to 3-dehydrocarnitine and is specific for L-carnitine and NAD+. The enzyme is formed by induction. L-carnitine and 3-dehydrocarnitine are inducers. Both substances can be utilized by the bacteria under aerobic conditions as sole source of carbon and nitrogen. After treatment of bacteria with lysozyme carnitine dehydrogenase is found in the supernatant of 90000 ×g and has been purified about 200-fold by means of ammonium sulfate fractionation (between 40 and 55% saturation), gel filtration (Sephadex G-200) and hydroxyl apatite chromatography. The purified enzyme did not react with D,L-S-hydroxybutyrate, L-lactate, ethanol, L-malate and D,L-isocitrate (final concentration 25 mM). The optimal temperature is 35° for the forward reaction (Q10 = 1.71 ; energy of activation 8.5kcal/mole) as well as the reverse reaction (Q10 = 1.99; energy of activation 8.2 kcal/mole). The oxidation reaction with carnitine as substrate exhibited optimum activity between pH 9.0 and 9.5. The reduction reaction with 3-dehydrocarnitine and NADH as substrates showed optimum activity at pH 7.0. The apparent Michaelis constants, Km, for the substrates carnitine and NAD+ and for the products of the reaction 3-dehydrocarnitine and NADH were determined. The pK/pH- and—log [ V/Km]/pH-profiles of the forward reaction allow the assumption of thiol groups in the active center of the enzyme. Analogues of L-carnitine (D-carnitine, glycine betaine and choline) are competitive inhibitors of T.-carnitine oxidation. The equilibrium constant of the reaction of earnitine dehydrogenase was determined and found to be 1.3 ×10-11 (standard error: ±0.5×10-11) at 30°. Possibilities of an optical test to determine T.-carnitine and 3-dehydrocarnitine using carnitine dehydrogenase are discussed. [ABSTRACT FROM AUTHOR]

The binding sites, to which [14C]arginine and [14C]valine are linked to a messenger-like RNA of Alcaligenes faecalis in the presence of ATP and a purified ‘polypeptide synthetase’ preparation from the same organism, have been identified. From a large scale incubation mixture, [14C]Arg-RNA was isolated and degraded with ribonuclease. By electrophoretic and chromatographic methods two compounds were obtained, CpUp-[14C]Arg, and CpUp-[14C]Arg-Cp. Evidence is presented indicating that the carboxylic group of the amino acid was bound in ester linkage to the hvdroxy1 in 2′-position of the uridylic ribose. The same compound were obtained when an RNA fraction from Escherichia coli was used. Similar experiment with [14C]valine yielded CpCp-[l4C]Val and CpCp-[14C]Val-Cp with either RNA fraction. With TYMV-RNA as acceptor, CpCp-[l4C]Val was identified. The possible significance of these results is discussed. [ABSTRACT FROM AUTHOR]

The primary structure of the wall peptidoglycans of Neisseria perflava, Moraxella glucidolytica and Pseudomonas alcaligenes is similar to those of the Enterobacteriaceae Proteus vulgaris and Escherichia coli, suggesting that the peptidoglycans of all gram-negative bacteria contain mesodiaminopimelic acid and belong to the same chemotype I. Differences are observed with regard to the thickness of the peptidoglycan layer in the cell envelopes, the extent of peptide crosslinking and the occurrence of N,O-diacetylmuramic acid residues. [ABSTRACT FROM AUTHOR]

The cell wall lipopolysaccharide constituent of Shigella flexneri, Salmonella typhimurium and Salmonella minnesota appears in the electron microscope as long slender filaments having a molecular weight of several millions. Such lipopolysaccharides are constituted of subunits held together by low-energy bonds of chelating and hydrophobic nature due to the lipid part of the molecule. Physicochemical studies gave molecular weights in the range of 18000 to 25000 for the subunits of S strains depending upon the bacterial species, and 10000 in the ease of the Salmonella minnesota R mutants. The subunits seem to be long ellipsoids of revolution made up of a lipid part and two polysaccharide side chains. Studies of the dissociation and the reassociation of the lipopolysaccharide subunits showed the existence of a cylindrical intermediate ‘unit structure’ having a molecular weight of about 5·105. The arrangement of the subunits in that unit structure seems to be of a micellar type, the lipids being located in the central part of this structure. This latter model is compatible with a skew arrangement of unit structures into the larger polymer molecules. [ABSTRACT FROM AUTHOR]

A benzene-utilizing strain of Moraxella B (genus/Acinetobacter) was isolated from Rhine water. Cell-free extracts of this bacterium, which is highly specific for the oxidation of benzene, require for this process catalytic amounts of NADH. This is regenerated during the course of the reaction by the dehydrogenation of cis-cyclohexadiene-diol to pyrocatechol. The oxygenase system contains nonheme-iron in the form of strongly bound Fe2+. It incorporates two atoms of oxygen simultaneously, as proven by isotope experiments; it is thus a dioxygenase. cis-l,2-Dihydroxy-dihydrobenzene was isolated as the first identifiable stable intermediate. This is further oxidized to pyrocatechol which is then eventually complexly metabolized via the 3-oxoadipic acid pathway. [ABSTRACT FROM AUTHOR]

The determination of the 2-keto-3-deoxyoctonic acid (KDO) content of a lipopolysaccharide obtained from Escherichia coli ATCC 12408 using the thiobarbituric acid and semicarbazide methods for its estimation points to the presence of a KDO trisaccharide unit in the structure. On partial hydrolysis of the lipopolysaccharide by the method of Painter, using polystyrene sulphonic acid, up to 60% of the KDO was lost. A core oligosaccharide, with a molecular weight in the region of 3500 to 5000 and containing heptose, glucose, galactose, KDO and phosphorus in the molar ratio of 2:1.44:0.6:0.3:1.3, was isolated on fractionation of the dialysate on Sephadex G-15. Sodium borohydride reduction of the oligosaccharide results in the loss of both reducing power and KDO, indicating a linear-type structure with KDO only at the reducing end. Removal of phosphate from the oligosaccharide had no significant effect on its molecular weight. Periodate oxidation, followed by borohydride reduction, and methylation studies showed the presence of certain structural features similar to those already found for the core region of lipopolysaccharides from other gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Studies were made to determine the effects of hexachlorophene on aerobic bacteria of normal human skin. A test group of adults exposed their toe webs to the exaggerated use of a detergent containing 3% hexachlorophene. A control group followed the same regimen with a similar detergent containing no hexachlorophene. A membrane filter culture technique was used to make semiquantitative and qualitative estimations of the skin bacteria present before and after detergent usage. Both groups of subjects had a significant decline in numbers of cutaneous diphtheroids upon detergent usage. The test subjects showed significantly decreased densitites of staphylococci accompanied by significantly increased numbers of Gram-negative bacilli, a trend not observed among the control subjects. When coagulase-negative staphylococci were inhibited, there resulted an emergence of the Enterobacter-Klebsiella and Pseudomonas groups of Gram-negative bacilli on a moist skin area of adults. [ABSTRACT FROM AUTHOR]

Fifty cases of Gram-negative folliculitis have been identified amongst 1200 new cases of acne vulgaris in a period of 4 years. Two clinical varieties are recognized. Type I, the more common, presents as superficial pustules, usually grouped around the nose and is associated with a lactose fermenting Gram-negative rod. Type II lesions are characterized by deep nodular and cystic lesions; Proteus appears to be the causative agent. The treatment of this condition is discussed. There has recently been a world-wide increase in systemic infections caused by Gram-negative organisms (Findland, Jones & Barnes, 1959; Barber, 1961; Johnstone, 1970; Adier, Martin & Findland, 1971). The widespread use of antibiotics effective predominantly against Gram-positive organisms has been incriminated as the probable cause for this shift. We previously reported a cutaneous example of antibiotic induced superinfection; namely. Gram-negative folliculitis complicating the treatment of acne vulgaris (Fulton et al., 1968). This syndrome consisted of the following: (1) an older aged acne patient who had been on antibiotics, usually tetracyclines, for prolonged periods, (2) pustular lesions grouped about the nose and fanning out on to the cheeks, (3) the recovery of Gram-negative lactose fermenting rods from the anterior nares and from one or more of the pustules, (4) histological evidence of an intrafollicular abscess without comedone formation and (5) clinical improvement following antibiotic therapy directed against the Gram-negative organisms. Our experience since has broadened to fifty patients. It is our intent in this report to delineate this syndrome from the viewpoint of diagnosis, pathogenesis and treatment. [ABSTRACT FROM AUTHOR]

When standard skin burns of mice were infected with a virulent strain of Pseudomonas aeruginosa there was rapid and extensive penetration of the burn and underlying tissues by the organisms. Under similar experimental conditions an avirulent strain of Ps. aeruginosa remained localized at the surface of the burned skin. In vitro experiments showed that heating did not make the proteins of skin more susceptible to hydrolysis by enzymes, since heated and unheated skin were hydrolysed to approximately the same extent by proteinases from both virulent and avirulent strains of Ps. aeruginosa. Burns of the skin are readily colonized by Ps. aeruginosa (Jackson, Lowbury & Topley, 1951; Markley et al., 1957; Tumbusch et al., 1961). In patients not receiving effective treatment bacteria can penetrate the burns and underlying tissues and may cause fatal septicaemia (Cason & Lowbury, 1968). In the present study the bacterial invasion of burned skin was followed by histological and immunofluorescent techniques, using two strains of Ps. aeruginosa, P14 (lethal for burned mice, Jones & Lowbury, 1966) and P2AB (not lethal for burned mice). These strains produced toxins of similar lethality, but P14 produced extracellular proteinases more rapidly than P2AB (Carney & Jones, 1968). In the present investigation normal and heat-damaged guinea-pig skin was compared in hydrolysis experiments using extracellular proteinases of Ps. aeruginosa P14 and P2AB. [ABSTRACT FROM AUTHOR]

The article focuses on treatment of various diseases and therapeutic use of different compounds. In Great Britain the initial treatment of previously untreated tuberculosis is still with the triple combination of streptomycin, para-aminosalicylic acid (PAS) and isoniazid. Rifampicin is bactericidal. It has antibacterial activity against Gram-positive cocci comparable with penicillin, but is also active against Gram-negative bacteria, particularly, Haemophilus influenzae and Neisseria Gonorrhoeae. However, its greatest importance is its antimycobacterial activity.

This article focuses on gram-negative bacilli that are found on the human skin. Unlike the staphylococci, Gram-negative bacilli are not often found in large numbers on normal human skin. This is what one should expect, for in suspensions of these organisms allowed to dry on skin or on glass, the great majority die when the suspending fluid evaporates to dryness. By contrast, the majority of staphylococcal cells survive such drying. Although Gram-negative bacilli, including Escherichia coli, Pseudomonas aeruginosa and Proteus spp. are sparse and probably easy to remove, nurses working in wards where infection with such organisms is common often carry them on their hands.

The article focuses on the outbreak of salmonella gastroenteritis in Sioux City, Iowa. The outbreak represents the strategic role of slicing equipment in restaurants and food catering establishments as a reservoir of contamination. Individuals with positive stool culture for Salmonella enteritidis, fever and diarrhea, or diarrhea or abdominal cramps within 100 hours of a meal are considered to have salmonellosis. Kitchen employees have been questioned about routine procedures of food preparation. It was found that the illness occurs exclusively among restaurant patrons who had eaten in the main dining rooms or at a banquet.

Provides information on a study that investigated the frequency of colonization of the respiratory tract with Gram-negative bacilli and the relation of such colonization to nosocomial infection in a group of patients admitted to a medical intensive care unit. Methodology of the study; Results and discussion on a study.

Provides information on the treatment of Gram-negative bacillary meningitis, associated with the central nervous system. Application of antimicrobial therapy in Gram-negative activity; Utilization of kanamycin and gentamicin as treatment for the condition; Effect of antibiotics on the central nervous system.

Discusses a study on fecal leukocytes in diarrheal illness. Examination of stools from subjects using methylene blue stain; Materials and methods used; Results of the study.

Provides information on a study that analyzed polymicrobial bloodstream infection in 46 patients over a period of one and one half years. Methodology of the study; Results and discussion on the study.

Describes an outbreak of nosocomial infections caused by non-pigmented Serratia marcescens. Background of Serratia marcescens; Characteristics of patients with positive cultures for Serratia; Environmental surveys for Serratia marcescens before Institutions of Control Measures; Importance of underlying host determinants in the occurrence of disease from exposure to Gram-negative bacilli.

During 12 selected years from 1933 to 1965, 337 patients were documented as having bacterial endocarditis at Boston City Hospital, 43 of them with 2 organisms and 10 with 3 in their blood, or heart valves, or both. Streptococcus viridans was the most frequent organism found and occurred in every year and Pneumococcus and Staphylococcus aureus in each year but one. The finding of Staph. aureus, gram-negative bacilli (not Salmonella or Shigella). Enterococcus, and Staph. epidermidis appeared to be related to extensive usage of antimicrobials and was predominantly nosocomial. Only two patients with Enterococcus and one in whom Staph. epidermidis as found were seen before 1947. Rheumatic valvular disease was present in more than two thirds of the patients with S. viridans or Staph. epidermidis but 4 only one third or less of those with other organisms. Staph. aureus, Enterococcus, and gram-negative bacilli more often affected patients over 60 and S. pyogenes and S. viridans, those under 40 years old. [ABSTRACT FROM AUTHOR]

Antibiograms were reviewed of all strains of Escherichia coli and Klebsiella­Enterobacter isolated from lesions of patients at the University of Washington Hospital, Seattle, from mid-1959 through 1968. No trend to increasing resistance to any of the chemotherapeutics tested was noted among the isolates of E. coli or Klebsiella­Enterobacter, and declining resistance was evident. E. coli showed an increase of strains resistant to none or only one of the seven agents and a decrease in multiply resistant strains. The frequency of E. coli bacteremia has not increased since 1959–1960 and 1961, and the antibiograms of organisms isolated from the blood generally coincided with the antibiograms of the total population. The incidences of Klebsiella­Enterobacter strains resistant to the seven chemotherapeutic agents also diminished as did that of multiply resistant strains. In contrast to E. coli, the frequency of klebsiella­enterobacter bacteremia did not diminish during the first 7 years; during the subsequent 3 years there was a marked decrease in frequency of positive blood cultures. The incidences of resistance to tetracycline and streptomycin may be associated with the amounts used per patient. [ABSTRACT FROM AUTHOR]

Describes a syndrome that is characterized by acute hypotension and shock and occurs during the course of bacteremia due to gram-negative microorganisms. Incidence of bacteremia and bacterial shock according to hospital services; Finding that the most frequent organism isolated in patients with shock was Escherichia coli.

Examines the frequency of urinary tract infection in a group of pregnant women. Character of bacteriuria in pregnancy; Percentage of patients with gram negative bacilluria; Bacteriuria developing after negative initial culture.

Compares single-disc and tube-dilution techniques used in determining antibiotic sensitivities of gram-negative pathogens. Correlation between disc and tube-dilution tests with tetracycline; Susceptibility of Gram-negative pathogens to a variety of antibiotics.

The article discusses the methods for controlling cross-infections caused by gram negative bacilli on the Pediatric Contagion Unit of Meadowbrook Hospital in Long Island, New York. Between March 1 and April 30, 1964, ten children who were admitted at the hospital because of capillary bronchiolitis or laryngotracheobronchitis developed gastroenteritis. The children, all under two years of age, developed severe vomiting, diarrhea and dehydration several days after their hospital admission. The possible etiologic agents for the disease were Aerobacter cloacae and Pseudomonas aeruginosa which were spread by contaminated equipment at the hospital. To prevent cross infection with gram negative bacilli the hospital decided to establish accurate cleaning and disinfection technics for hospital equipment.

This article describes a bacterial disease of dahlias caused by Pseudomonas marginalis. It takes the form of a wet, black rot and is most troublesome on young cuttings in the propagation bed. Specimens of the infected cuttings showed a flaccidity of the stem together with a slight shrivelling and drying of the base. The appearance of the tissues suggested a bacterial disease. A gram-negative bacterium was present in profusion in sap expressed from the affected stem tissues. In addition, the widespread nature of the potential infection suggested that the source might be the greenhouse water tank.

A study was made to determine the effect of lysozyme on certain oral organisms after exposure to guinea pig complement (C'). No effect was observed on gram-positive streptococci or strains of Actinomyces whether pretreated with C' or not. Strains of Veillonella, a gram-negative organism, were partially lysed by the synergistic action of C' and lysozyme. This reaction is described in detail. [ABSTRACT FROM AUTHOR]

The article focuses on the synthesis of mucinous polysaccharides from sucrose by oral bacteria. The conclusions are that Streptococcus salivarius and gram-negative diplococci, which produce levan and amylpectin respectively, are the only bacterial types that can synthesize mucinous polysaccharides from sucrose and that these polysaccharides are not part of the process of dental mucinous plaque formation.

The article focuses on the detection of pleuropneumonia-like organisms (PPLO) in human saliva. It states that these organisms are also found in high incidence in the genitourinary tract. It mentions that there appeared to be no correlation between the presence of PPLO and of the lactobacillus count. It comments on efforts to suppress the growth of gram-positive and gram-negative bacteria while cultivating PPLO in Petri dish cultures.

From the lipopolysaccharide of the gram-negative bacterium Rhodopseudomonas capsulata (Athiorhodaceae) a lipophilic sugar was isolated by chromatographic procedures and characterized by mass spectrometry as belonging to the group of 3-O-methyl-6-deoxy-hexoses. Demethylation showed that the parental sugar had the same properties in borate electrophoresis as rhamnose. Comparison with an authentic sample of 3-O-methyl-rhamnose in gas liquid chromatography, paper chromatography and borate electrophoresis showed that the sugar under examination is 3-O-methylrhamnose (acofriose). Investigation of its optical rotation indicates that the sugar has the L-configuration. L-Acofriose (3-O-methyl-L-rhamnose) has not hitherto been found in lipopolysaccharides of gram-negative bacteria. [ABSTRACT FROM AUTHOR]

The inactivation of glutamine synthetase in vivo on addition of ammonium ions to the culture medium was studied in different microorganisms. Only those belonging to the family of Entero-bacterioceae showed inactivation. The transfer activity of the enzyme was much less affected than the synthetic one. As in Escherichia coli, the glutamine synthetase of Salmonella typhimurium could be inactivated in vitro in a system requiring glutamine, ATP, Mg&sup2+; and an enzyme. The inactivating enzymes of E. coli and S. typhimurium have been separated and cross-tested against their synthetases. The inactivating enzymes inactivated both glutamine synthetases in the in vitro inactivation process. In contrast, synthetases of microorganisms which did not exhibit in vivo inactivation were not affected by these inactivating enzymes. The fact that only glutamine synthetases of Enterobacteriaceae could be inactivated suggests that this regulatory mechanism is limited to a group of organisms possibly derived from the same ancestor. [ABSTRACT FROM AUTHOR]

Presents a case study of a patient diagnosed with septic shock. Information on a laparotomy underwent by the patient; Hemodynamic and biochemical data of the patient; Role of gram negative bacteremia with endotoxin production in the presence of septic shock.

The article presents the results of a study which investigated the establishment of typical microbiota in the mouths of human infants. An overview of related previous research is provided, along with details of the experimental protocol. Fusiform Gram-negative bacteria, including anaerobic strains, were found in the saliva samples of most healthy infants by six months of age.