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The requirement of ovalbumin for the growth of group A hemolytic Streptococcus in a synthetic medium.

Crystalline ovalbumin, when heated under controlled conditions, promoted growth of Streptococcus hemolyticus in a synthetic medium. A similar activation of albumin also was produced by ultraviolet irradiation or by shaking under nitrogen. Untreated albumin failed to permit growth under the same conditions. The activity of treated albumin was destroyed by aeration or by reaction with iodoacetate. The data suggest that the activity of ovalbumin for the streptococcus depends on the presence of "exposed" SH groups. However, other sulfhydryl-containing compounds (thioglycolate, glutathione, cysteine) could not replace ovalbumin. A number of crude and crystalline proteins, and di- and tripeptides were inactive. Strepogenin and crystalline bovine serum albumin produced a weak growth response on extended incubation. Approximately 50 per cent of the original protein in the culture disappeared during growth. Ovalbumin labelled with C(14) was added to the synthetic medium. After growth of the culture the isotope was found associated with the cells and in the culture fluid in both dialyzable and non-dialyzable forms. Under the conditions described, luxuriant growth of 15 strains (10 serological types) of Group A streptococci was obtained in 10 hours from small inocula. The growth was capable of repeated subcultivation.

Albumins↗

mef(A), mef(E) and a new mef allele in macrolide-resistant Streptococcus spp. isolates from Norway.

OBJECTIVES: To type mef genes in a nationwide collection of clinical isolates of Streptococcus pneumoniae and Streptococcus pyogenes as well as pharyngeal carrier strains of viridans streptococci in Norway. METHODS: Erythromycin-resistant mef-positive multilocus sequence-typed (MLST) clinical isolates of S. pneumoniae (n = 36) and S. pyogenes (n = 12) from the National Surveillance Program for Antimicrobial Resistance (NORM) as well as viridans streptococci (n = 20) from healthy adults were included. PCR-amplified mef genes were initially discriminated by BamHI digestion. Selected mef genes from representatives of different sequence types (STs) of S. pneumoniae (n = 11) and S. pyogenes (n = 4), and viridans group streptococcal species (n = 8) were typed by sequencing and their strains examined for co-resistances. Hydropathy plots of different mef-encoded proteins were performed. RESULTS: A predominance of mef(A) was detected in S. pneumoniae (23/36) and S. pyogenes (9/12) due to the clonal spread of ST9 and ST39, respectively. mef(E) was the most widely distributed mef determinant occurring in nine different STs of S. pneumoniae and in four different viridans species. A new mef allele was identified in two STs of S. pyogenes. CONCLUSIONS: mef(E) is the most widely distributed mef determinant in Norwegian clinical strains of S. pneumoniae and pharyngeal carrier strains of various viridans streptococci. However, mef(A) is more prevalent in S. pneumoniae and S. pyogenes due to clonal spread. A new mef allele was found in two different STs of S. pyogenes.

Amino Acid Sequence↗

Conjugal transfer of group B streptococcal plasmids and comobilization of Escherichia coli-Streptococcus shuttle plasmids to Lactobacillus plantarum.

The antibiotic resistance group B streptococcal plasmids, pIP501 and pVA797, were conjugally transferred from Streptococcus faecalis to Lactobacillus plantarum. The Escherichia coli-Streptococcus shuttle plasmids, pVA838 and pSA3, were mobilized from S. sanguis to L. plantarum by pVA797 via cointegrate formation. pVA838 readily resolved from pVA797 and was present in L. plantarum as deletion derivatives. The pVA797::pSA3 cointegrate failed to resolve in L. plantarum.

Conjugation, Genetic↗

Selective adsorption of heterophile polyglycerophosphate antigen from antigen extracts of Streptococcus mutans and other gram-positive bacteria.

Hot saline extracts of Streptococcus mutans have been shown to contain antigenic substances which occasionally react nonspecifically with some antisera against whole cells of various serological groups and types of streptococci. Chromatography of the extract of S. mutans strain MT703 (serotype e) on a diethylaminoethyl-Sephadex A-25 column gave two principal antigens. One antigen was eluted without adsorption to the resin and was identified as the serotype-specific polysaccharide. The other antigen, which contained a large quantity of phosphorus, was absorbed to and released from the resin by gradient elution. It was reactive against the antisera specific for polyglycerophosphate (PGP) from group A Streptococcus pyogenes and/or S. mutans strain Ingbritt (type c). The PGP antigen was further purified by gel filtration with Sephadex G-75. Two peaks, PGP-1, and PGP-2, were obtained. Each possessed the same antigenic specificity to anti-PGP serum as shown by immunodiffusion. Chemical analyses revealed that the molar ratio of phosphorus to glycerol in both was about 1:1, although the protein content between the two was significantly different. PGP antigen was found to be widely distributed in hot saline extracts from various gram-positive bacteria, with a few exceptions. However, all gram-negative bacteria examined were free of PGP. The PGP in the hot saline extracts of various gram-positive bacteria possessed an essentially identical antigenic specificity. The addition of diethylaminoethyl-Sephadex A-25 resin to hot saline extracts successfully removed the cross-reacting PGP antigen. After adsorption of the extract from S. mutans, the supernatant contained only type-specific polysaccharide antigen, except type b, in which both type b-specific polysaccharide and PGP antigens were absorbed with the resin. This simple procedure should be useful for the removal of the PGP-type teichoic acid from antigen extracts of bacteria that contain uncharged polysaccharides.

Antigens, Bacterial↗

Dissemination of the phage-associated novel superantigen gene speL in recent invasive and noninvasive Streptococcus pyogenes M3/T3 isolates in Japan.

In Japan, more than 10% of streptococcal toxic shock-like syndrome (TSLS) cases have been caused by Streptococcus pyogenes M3/T3 isolates since the first reported TSLS case in 1992. Most M3/T3 isolates from TSLS or severe invasive infection cases during 1992 to 2001 and those from noninvasive cases during this period are indistinguishable in pulsed-field gel electropherograms. The longest fragments of these recent isolates were 300 kb in size, whereas those of isolates recovered during or before 1973 were 260 kb in size. These 260- and 300-kb fragments hybridized to each other, suggesting the acquisition of an about 40-kb fragment by the recent isolates. The whole part of the acquired fragment was cloned from the first Japanese TSLS isolate, NIH1, and its nucleotide sequence was determined. The 41,796-bp fragment is temperate phage phiNIH1.1, containing a new superantigen gene speL near its right attachment site. The C-terminal part of the deduced amino acid sequence of speL has 48 and 46% similarity with well-characterized erythrogenic toxin SpeC and the most potent superantigen, SmeZ-2, respectively. None of 10 T3 isolates recovered during or before 1973 has speL, whereas all of 18 M3/T3 isolates recovered during or after 1992 and, surprisingly, Streptococcus equi subsp. equi ATCC 9527 do have this gene. Though plaques could not be obtained from phiNIH1.1, its DNA became detectable from the phage particle fraction upon mitomycin C induction, showing that this phage is not defective. A horizontal transfer of the phage carrying speL may explain the observed change in M3/T3 S. pyogenes isolates in Japan.

Amino Acid Sequence↗

INTRACELLULAR M PROTEIN OF GROUP A STREPTOCOCCUS.

Fox, Eugene N. (University of Chicago, Chicago, Ill.). Intracellular M protein of group A Streptococcus. J. Bacteriol. 85:536-540. 1963.-A heat-labile M protein antigen in protoplasts of a type 14 strain of group A Streptococcus has been demonstrated in a soluble form in the cytoplasm, and also bound to the protoplasmic membrane. When trypsinized whole cells (from which the M protein on the cell wall had been digested) or protoplasts were extracted with hot HCl, no M protein antigen was detected, although the antigen was routinely extracted from the cell walls of normal streptococci by the hot acid procedure. Various serological techniques, including the use of fluorescein-labeled type-specific antisera, were employed to demonstrate the M antigen in association with the membrane from osmotically lysed protoplasts.

Bacterial Proteins↗

METABOLISM OF INTRACELLULAR POLYSACCHARIDE BY STREPTOCOCCUS MITIS AND ITS RELATION TO INDUCIBLE ENZYME FORMATION.

Gibbons, R. J. (Forsyth Dental Center, Boston Mass.). Metabolism of intracellular polysaccharide by Streptococcus mitis and its relation to inducible enzyme formation. J. Bacteriol. 87:1512-1520. 1964.-The synthesis and catabolism of an intracellular iodine staining polysaccharide produced from glucose by Streptococcus mitis was investigated. Approximately 15% of the total glucose metabolized by buffered suspensions of S. mitis was assimilated. Over 90% of the assimilated glucose was converted into a polysaccharide of the glycogen-amylopectin type. Use of uniformly labeled C(14)-glucose provided a convenient method for determining polysaccharide accumulation in this organism. Glucose assimilation occurred at a rate of over 80 mug of glucose per hr per 100 mug of starting dry cell weight. Prolonged assimilation produced cells containing over 50% polysaccharide on a dry weight basis. Accumulated polysaccharide was catabolized at the same rate when the organism was suspended in buffer, sugar-free broth, or sugar-free broth containing thiomethyl galactoside. Metabolic intermediates produced from polysaccharide catabolism did not markedly repress inducible enzyme synthesis. The last glucose molecules incorporated into polysaccharide were among the first molecules to be removed during catabolism. Catabolism of polysaccharide provides S. mitis with energy in a utilizable form, for cells containing polysaccharide increased in beta-galactosidase activity when induced with thiomethyl galactoside in the absence of an exogenous energy source. Cells devoid of polysaccharide, and a polysaccharide-negative variant of S. mitis did not increase in beta-galactosidase activity when induced in a similar manner. It appears that the intracellular polysaccharide is the sole substrate for the endogenous metabolism of S. mitis.

Carbohydrate Metabolism↗

AMINO GROUP FORMATION AND GLUTAMATE SYNTHESIS IN STREPTOCOCCUS BOVIS.

Burchall, J. J. (University of Illinois, Urbana), R. A. Niederman, and M. J. Wolin. Amino group formation and glutamate synthesis in Streptococcus bovis. J. Bacteriol. 88:1038-1044. 1964.-Extracts of Streptococcus bovis grown on NH(4) (+) as a nitrogen source contain a nicotinamide adenine dinucleotide phosphate (NADP)-linked glutamic dehydrogenase and are devoid of alanine dehydrogenase, other amino acid dehydrohygenases, and aspartase. A potential source of reduced nicotinamide adenine dinucleotide phosphate for glutamate synthesis is a NADP and nicotinamide adenine dinucleotide (NAD)-linked glyceraldehyde-3-phosphate dehydrogenase present in the extracts. Experiments with C(14)-labeled glucose and NaHCO(3) indicate that the glutamate carbon skeleton is synthesized by a tricarboxylic acid pathway. The synthesis of the carbon skeleton of glutamate is repressed when glutamate or casein hydrolysate supplement the NH(4) (+)-containing growth medium. Repression of glutamic dehydrogenase and a NAD-linked isocitric dehydrogenase occurs only when complex nitrogen sources, but not when free amino acids, are added to the growth medium.

Amino Acids↗

EFFECT OF AMINO ACIDS ON STEADY-STATE GROWTH OF A GROUP A HEMOLYTIC STREPTOCOCCUS.

Davies, Helen C. (University of Pennsylvania, Philadelphia), Fred Karush, and Joanne H. Rudd. Effect of amino acids on steady-state growth of a group A hemolytic streptococcus. J. Bacteriol. 89:421-427. 1965.-A study has been made of amino acid utilization by a strain of type 4, group A streptococcus growing under steady-state conditions in a continuous-culture device and supplied with a completely synthetic medium. At a fixed growth rate, corresponding to a generation of time of 84 min, and with the pH maintained constant at 7.4, the bacterial turbidity was made dependent on the concentration of one of the amino acids of the defined medium. Under these conditions, the extracellular concentration of the limiting amino acid is fixed by the preset growth rate. The steady-state concentration of each of 14 essential l-amino acids was measured by means of C(14)-labeled amino acids in such limited cultures. At approximately equal turbidities, these concentrations ranged from 1.6 x 10(-6)m for methionine to 4.3 x 10(-4)m for glutamic acid. The rates of utilization of the amino acids ranged from 26 mmumoles per mg (dry weight) of bacteria per hr for histidine to 310 mmumoles per mg (dry weight) of bacteria per hr for glutamic acid. The percentage of the limiting amino acid used varied from 95% for threonine and methionine to 43% for gluamic acid. The rate of utilization of the limiting amino acid at unit concentration (tmoles per gram per hour per m) differed by a factor of 27 between extremes. These observations reflect the variation in the capacity of this streptococcal cell to take up and use different amino acids.

Acids↗

EFFECT OF PARTIALLY PURIFIED STREPTOCOCCAL M PROTEIN ON THE IN VITRO PHAGOCYTOSIS OF STREPTOCOCCUS PYOGENES.

Domingue, Gerald J. (Tulane University, New Orleans, La.), and William A. Pierce, Jr. Effect of partially purified streptococcal M protein on the in vitro phagocytosis of Streptococcus pyogenes. J. Bacteriol. 89:583-588. 1965.-M protein from Streptococcus pyogenes strain Bailey type 12 was adsorbed onto cells of a glossy mutant of this strain. Phagocytosis experiments were performed in vitro with rabbit peritoneal polymorphonuclear leukocytes. Direct microscopic counts suggested M protein-treated cells were more resistant to phagocytosis than were untreated cells. With the Cohn and Morse technique for evaluating quantitatively the fate of bacteria during phagocytosis, there was observed a more rapid drop in total and extracellular counts of treated, as compared with untreated, cells. Experiments with radioactively labeled streptococci showed that M-treated cells were more readily destroyed within leukocytes than were nontreated glossy streptococci, which suggested a reason for the scarcity of treated streptococci in direct microscopic counts.

Agglutination↗

Laboratory evaluation of a rapid four-hour serological grouping of groups A,B,C, and G beta-streptococci by the Phadebact streptococcus test.

Grouping of beta-hemolytic streptococcal isolates by staphylococcal coagglutination was performed with the Phadebact Streptococcus Test to determine whether such isolates could be accurately grouped serologically with 4 h after examination of the primary isolation plates. Of 132 clinical isolates, 131 were correctly grouped by the Phadebact method using the Lancefield precipitation method as the accepted standard. Of the correctly grouped streptococci, 119 were definitively grouped within 4 h after examination of the primary plates, and the remaining 12 isolates were grouped within 24 h. Since the Phadebact Streptococcus Test contains coagglutination reagents for groups A, B, C, and G, those isolates that failed to react were considered as positive for groups other than the four included in the test system. There were 23 such isolates in this study. Lancefield grouping of these isolates indicated that nine were group F, five were group D, and the remaining nine were not groupable with the Lancefield reagents employed in this study. The one Phadebact "failure" involved an isolate that produced a 4 + reaction with the Phadebact group A reagent and a 4 + reaction with Lancefield group F reagent.

Agglutination↗

Studies concerning the glucosyltransferase of Streptococcus sanguis.

We have shown in previous studies that the glucosyltransferase (Gtf) enzymes of Streptococcus mutans have distinct properties when adsorbed to a surface. In the present study, we compared the activity of Gtf from Streptococcus sanguis, designated GtfSs, in solution and on the surface of saliva-coated hydroxyapatite (sHA) beads, and determined the ability of its product glucan to support the adherence of oral microorganisms. Gtf from S. sanguis 804 NCTC 10904 was purified from culture supernatant fluids by means of hydroxyapatite chromatography. Enzyme and the substrate were prepared in buffers at pH values from 3.5 to 7.5. Maximum activity of GtfSs occurred between pH 5.5 and pH 6.5, whether in solution or adsorbed onto a surface. The solubilized and insolubilized enzymes showed highest activity at 40 degrees C; activity was reduced by 50(+/-2)% at 20 and 30 degrees C. The enzyme did not form glucans in either phase at 10 or 60 degrees C. The K(m), determined from Lineweaver-Burk plots, for the enzyme in solution was 4.3(+/-0.4) mmol/l sucrose, and the K(m) for the enzyme on sHA beads was 5.0(+/-1.0) mmol/l sucrose. The ability of the GtfSs glucan synthesized on the surface of sHA beads to support the adherence of oral bacteria was investigated. (3)H-thymidine-labeled bacteria (S. mutans GS-5, S. sobrinus 6715, S. sobrinus 6716, S. sanguis 10904, Actinomyces viscosus OMZ105E, A. viscosus 2085, and A. viscosus 2086) were incubated with sHA beads coated with GtfSs glucan. S. mutans GS-5 displayed the highest level of binding numerically. These results show that the GtfSs of S. sanguis is active on sHA beads, that the pH optimum for activity on a surface differs slightly from that in solution, and that its product glucan can support the adherence of oral microorganisms.

Actinomyces viscosus↗

[Phenotypic characterization of erythromycin resistance in strains of the genus Streptococcus isolated from clinical specimens].

There are presently two recognized mechanisms of resistance to macrolide antibiotics in species of the genus Streptococcus: target modification and efflux. Target modification occurs in the ribosomes through the production of a ribosomal methylase codified for the erm genes and it is phenotypically known as MLSB resistance. Expression of MLSB resistance can be inducible or constitutive. Active efflux has been recently described in S. pyogenes and S. pneumoniae, and its expression is known as M phenotype. We studied the susceptibility, by determining the MIC using agar dilution, to penicillin, erythromycin and clindamycin, of 295 strains of the genus Streptococcus clinically isolated from 1993 to 1996 (70 S. pyogenes, 81 S. pneumoniae, 37 viridans group, and 107 S. milleri). We also studied the phenotype pattern of erythromycin-clindamycin resistance in the strains resistant to erythromycin by using the double-disc test. We found a 17.2% resistance to erythromycin and a 12.5% resistance to clindamycin. The M phenotype, initially described in S. pyogenes, was also observed in 6.6% of our S. pneumoniae strains, 25% of S. viridans spp., and 4.8% in the S. milleri group.

Anti-Bacterial Agents↗

Streptococcus milleri: an organism for head and neck infections and abscess.

BACKGROUND: Streptococcus milleri, a commensal organism, has the potential to cause significant morbidity. There is a paucity of published data regarding this organism in the head and neck. OBJECTIVES: To identify and assess the presentation, treatment, and outcomes of pediatric patients affected by this pathogen. STUDY DESIGN: Review of the Department of Pathology database at Children's Hospital of Wisconsin, Milwaukee, between 1997 and 1999 identified 26 patients with cultures positive for S milleri group (SMG) bacteria. Retrospective chart analysis examined the demographic data, site of origin of infection, additional organisms cultured, symptoms, treatments, and complications. RESULTS: Sixteen patients had SMG infections involving the head and neck region. Sites of origin included the paranasal sinuses, dental, facial soft tissues, deep neck spaces, peritonsillar region, and a tracheostomy site. The paranasal sinuses were the most common site in 37% (6/16). Streptococcus milleri was the only isolate in 69% (11) of the infections. Significant local extension occurred in 56% (9/16) of the patients and included the orbit, skull base, cranium, and deep neck spaces. All patients had surgical drainage and 15 also received intravenous antibiotic treatment. One complication of osteomyelitis of the frontal bone occurred with resolution after surgical debridement and intravenous antibiotic treatment. CONCLUSIONS: Streptococcus milleri can be an aggressive pathogen in the head and neck with a propensity for abscess formation and local extension of the infection in a pediatric population. Surgical drainage with antibiotics is generally successful in management of the condition. However, emerging penicillin resistance and the ability for local extension require suspicion of incomplete treatment if clinical symptoms persist.

Abscess↗

Streptococcus bovis bacteremia and underlying gastrointestinal neoplasms.

Two patients are described in whom Streptococcus bovis bacteremia was the only clue to the presence of a colonic neoplasm. A third patient had the rare association of gastric carcinoma and Streptococcus bovis bacteremia that followed an operation for the carcinoma. The need for both complete gastrointestinal survey in patients with Streptococcus bovis bacteremia and administration of appropriate antibiotic prophylaxis during surgical manipulation is emphasized.

Aged↗

Streptococcus sanguis bacteremia and colorectal cancer: a case report.

Streptococcus sanguis, usually considered a nonpathogen of the oral cavity, was isolated from blood cultures from a patient who was subsequently found to have a cecal adenocarcinoma. Further studies are needed to determine if Streptococcus sanguis infections have diagnostic implications similar to those of Streptococcus bovis.

Adenocarcinoma↗

In situ reconstruction of septic aortic pseudoaneurysm due to Salmonella or Streptococcus microbial aortitis: long-term follow-up.

OBJECTIVE: This study was undertaken to illustrate the safety of in situ reconstruction of septic aortic pseudoaneurysm (SAP) secondary to microbial aortitis, with or without long-term antibiotic treatment. METHODS: Data for patients with SAP (11 abdominal, 4 thoracic) operated on between 1993 and 1999 were reviewed. Computed tomography and aortography showed septic pseudoaneurysm in all patients before surgery. After diagnosis of SAP, all patients underwent aneurysm resection and extensive debridement, with in situ prosthetic grafting or patch repair angioplasty. The graft in 10 of the 11 patients with abdominal SAP was also wrapped with an omental pedicle. In vitro active parenteral antibiotic therapy was prescribed for all patients for at least 2 to 8 weeks after surgery. RESULTS: All 15 patients had positive preoperative blood cultures or intraoperative tissue cultures for Salmonella spp (n = 12), viridans Streptococcus (n = 1), group G Streptococcus (n = 1), or Streptococcus pneumoniae (n = 1). There were two perioperative deaths (13.3%), one 6 days after surgery and the other 19 days after surgery, and two late deaths, at 8 and 10 months after surgery, neither of which was related to aortic repair. One patient was unavailable for follow-up. The other 10 patients have been regularly followed up with abdominal ultrasound or computed tomography (mean, 84 months; range, 47-118 months). To date, there has been no graft infection, thrombosis, false aneurysm, or subsequent aortic surgery in these 10 patients. CONCLUSION: SAP due to Salmonella and streptococcal microbial aortitis can be successfully treated with resection of the aneurysm and extensive debridement, followed by in situ prosthetic graft interposition or patch repair aortoplasty. This is a safe and effective treatment that may result in complete remission of SAP. Postoperative parenteral antibiotic therapy should be continued for 2 to 8 weeks. Although usually recommended, lifelong suppressive antibiotic therapy appears to be nonessential with this approach.

Aged↗

Clinical characteristics of necrotizing fasciitis caused by group G Streptococcus: case report and review of the literature.

A 52-y-old diabetic male developed severe necrotizing fasciitis due to group G Streptococcus. A review of the English language literature revealed 8 additional cases. The mean age of the total of 9 cases was 65.5 y (range: 49-80 y) and the majority (n = 5; 55.6%) had no comorbid conditions. The duration of symptoms prior to presentation was 1-5 d (mean +/- SD = 2.5 +/- 1.5 d). Presenting manifestations were swelling with redness (6/6 cases; 100%), severe pain (5/6 cases; 83.3%) and blister formation (3/6 cases; 50%); blisters developed eventually in 5/6 (88.3%) patients. Muscle involvement was noted in 2 patients (22.2%). Progression to toxic shock-like syndrome occurred in 3 cases (33.3%). The organism was isolated from the involved sites in all cases. Bacteremia was documented in 1/3 patients. Treatment included antibiotics (n = 9) and varying degrees of surgical debridement (n = 8). The mortality rate was 33.3%; all patients who died developed toxic shock-like syndrome. These findings illustrate that, similar to Streptococcus pyogenes-induced fasciitis, necrotizing fasciitis due to group G Streptococcus can be severe and life-threatening. Early diagnosis, immediate surgical debridement and antibiotic therapy are essential in order to improve the outcome.

Aged↗