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Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new satellitism test designed to facilitate the isolation and identification of Haemophilus influenzae and Haemophilus parainfluenzae is described. In the basal medium, nicotinamide adenine dinucleotide is incorporated at a concentration of 0.2 mug per ml, an amount adequate for H. influenzae but not for H. parainfluenzae. Two disks are placed on the surface of the medium, one disk being impregnated with 60 mug of hemin and the other with 15 mug of nicotinamide adenine dinucleotide. Under these conditions, H. influenzae strains grow around the hemin disk only and the majority of H. parainfluenzae grow around the nicotinamide adenine dinucleotide disk. This procedure gives results which are more clear cut than other established methods, especially in sputum culture.
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PMID:New satellitism test for isolation and identification of Haemophilus influenzae and Haemophilus parainfluenzae in sputum. 17 Mar 4

A method was devised to test the growth-promoting ability of a broth medium. The "dilute to extinction" method determines the inoculum required to develop heavy turbidity in a broth with overnight incubation. A statistical method using Poisson distribution was used to show that a single Haemophilus cell can develop heavy turbidity in an optimal broth. The dilute to extinction method was used to evaluate the shelf life of stored media, to titrate the growth factor requirements of Haemophilus, and to evaluate the use of purified hemin and nicotinamide adenine dinucleotide in a broth medium for the growth of Haemophilus. Of the media tested, the most suitable formulation was Mueller-Hinton broth supplemented with 10 microgram of hemin and 10 microgram of nicotinamide adenine dinucleotide per ml. The dilute to extinction method appears to be especially useful in the development of broth media for fastidious organisms. The method could also be used to assure the quality of other broth media which are required to support the growth of small inocula in the clinical or research laboratory.
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PMID:Method for evaluating broth culture media: application to Haemophilus. 21 1

The radiometric detection of various Haemophilus species was studied in simulated blood cultures and in blood culture media without added blood, but supplemented with nicotinamide-adenine dinucleotide (NAD) or hemin, or both. Haemophilus aphrophilus was the only species studied that was radiometrically detectable without added blood or NAD. All other species studied (Haemophilus influenzae, Haemophilus parainfluenzae, Haemophilus haemolyticus, and Haemophilus parahaemolyticus) required either added NAD, whole blood, or washed blood cells for growth and radiometric detection. The results of this study and extensive experience with clinical specimens show that the radiometric system is an effective means of rapidly detecting Haemophilus in blood cultures, but it is essential that it be used in conjunction with a subculture three to five days after inoculation.
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PMID:Radiometric detection of Haemophilus in simulated blood cultures. 21 44

The isolation, characterization, and identification of a microorganism isolated from gastrointestinal tracts of rabbits with mucoid enteritis are described. The isolated organism did not grow on standard media. This organism grew around colonies of Staphylococcus aureus and Lactobacillus desidiosus and around disks saturated with diphosphopyridin nucleotide (factor V) on brain heart infusion agar. The growth of this organism was also observed on media supplemented with beta-nicotinamide adenine dinucleotide. The organism appeared as gram-negative, pleomorphic rods or coccobacilli. It was positive for urease, oxidase, catalase, glycosidases, porphyrin, and indole, and it fermented glucose and sucrose. All of these characteristics suggest that the organism is a member of the genus Haemophilus. Because of its isolation from rabbits and differences in some characteristics from other species of this genus, the name Haemophilus paracuniculus is proposed for this organism.
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PMID:Characterization of a Haemophilus paracuniculus isolated from gastrointestinal tracts of rabbits with mucoid enteritis. 42 39

Historically, members of the family Pasteurellaceae were classified on the basis of a limited number of phenotypic characteristics. In particular, organisms were assigned to the family on the basis of their requirements for the growth factors hemin and/or nicotinamide adenine dinucleotide and on the basis of their ability to cause disease in vertebrates. More recent genotypic studies have shown that many members of the family Pasteurellaceae have been misclassified. In this paper we review some of the current taxonomic methods which can be used to emend the classification of Haemophilus, Actinobacillus and Pasteurella spp. and suggest some approaches and criteria for restructuring the family Pasteurellaceae.
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PMID:The family Pasteurellaceae: modern approaches to taxonomy. 169 67

Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acetylpyridine riboside, and 3-aminopyridine riboside were prepared from their corresponding NAD analogs. These compounds and several other nicotinamide riboside analogs were evaluated for their ability to support the growth of H. influenzae and for their ability to block the uptake of [carbonyl-14C]nicotinamide riboside by H. influenzae. 3-Aminopyridine riboside blocked the uptake of [carbonyl-14C]nicotinamide riboside and inhibited the growth of H. influenzae when NAD, nicotinamide mononucleotide, or nicotinamide riboside served as the V factor. The antibacterial activity of 3-aminopyridine riboside was found to be specific for H. influenzae but had no effect on the growth of Staphylococcus aureus or Escherichia coli. In additional experiments by reversed-phase high-performance liquid chromatography, it was determined that whole cells of H. influenzae degrade 3-aminopyridine adenine dinucleotide to 3-aminopyridine riboside, which is then internalized. Inside the cell, 3-aminopyridine riboside has the ability to interfere with the growth of H. influenzae by an undetermined mechanism.
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PMID:In vitro evaluation of nicotinamide riboside analogs against Haemophilus influenzae. 214

A variety of biologically important pyridine nucleotides and precursors were examined for their capacities to satisfy the V-factor requirement of 30 strains of porcine haemophili. Of the compounds tested, only NAD, NMN and nicotinamide riboside (NR) supported the growth of all strains; NADP supported the growth of only the type strain of Haemophilus parasuis. Further studies with the H. parasuis type strain and the neotype strain of H. pleuropneumoniae demonstrated that, during growth, these organisms exhibited affinities for NMN that were greater than those for NAD; the affinity of H. pleuropneumoniae for NR was similar to that for NMN, whereas H. parasuis exhibited relatively low affinity for NR. With either organism, equimolar amounts of NAD and NMN supported the production of approximately equal amounts of biomass whereas growth yields were substantially lower when NR was the pyridine nucleotide source. When either organism was grown in the presence of excess exogenous [carbonyl-14C]NAD, cessation of growth was accompanied by the apparent exhaustion of the NAD supply. Approximately 80% of the radioactivity added as [14C]NAD could be recovered as extracellular [14C]nicotinamide and the majority of the assimilated radioactive material was present intracellularly in the form of a [14C]NAD(P) pool. The results are discussed in terms of the structural features required of a pyridine compound for it to support the growth of porcine haemophili, the capacity of these organisms to compete for pyridine nucleotide sources in vivo, and possible mechanisms involved in the assimilation of such compounds.
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PMID:Defining the metabolic and growth responses of porcine haemophili to exogenous pyridine nucleotides and precursors. 294 35

A variety of biologically important pyridine nucleotides and precursors were examined for their capacities to serve as substrates for the synthesis of NAD by cell fractions derived from Haemophilus parasuis and H. pleuropneumoniae. Of the compounds tested, only NMN and nicotinamide riboside were converted to NAD. These reactions required ATP as co-substrate, and fractions from both organisms could also catalyze the ATP-dependent synthesis of NADP from NAD. In the absence of ATP, and depending on the pyridine compound under study, NAD, NMN, nicotinamide riboside, and also nicotinamide, were detected as products of catabolism. It is concluded that these haemophili possess either three-membered pyridine nucleotide cycles or two-membered cycles with synthetic branches originating with nicotinamide riboside. It is also possible that the pyridine nucleotide cycles of both organisms have nonrecycling branches resulting in the "waste" of usable pyridine compound in the form of nicotinamide.
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PMID:Pyridine nucleotide metabolism by extracts derived from Haemophilus parasuis and H. pleuropneumoniae. 294 87

The utilization of exogenous nicotinamide adenine dinucleotide (NAD) by Haemophilus parainfluenzae was studied in suspensions of whole cells using radiolabelled NAD, nicotinamide mononucleotide (NMN), and nicotinamide ribonucleoside (NR). The utilization of these compounds by H. parainfluenzae has the following characteristics. (1) NAD is not taken up intact, but rather is degraded to NMN or NR prior to internalization. (2) Uptake is carrier-mediated and energy-dependent with saturation kinetics. (3) There is specificity for the beta-configuration of the glycopyridine linkage. (4) An intact carboxamide groups is required on the pyridine ring. The intracellular metabolism of NAD was studied in crude cell extracts and in whole cells using carbonyl-14C-labelled NR, NMN, NAD, nicotinamide, and nicotinic acid as substrates in separate experiments. A synthetic pathway from NR through NMN to NAD that requires Mg2+ and ATP was demonstrated. Nicotinamide was found as an end-product of NAD degradation. Nicotinic acid mononucleotide and nicotinic acid adenine dinucleotide were not found as intermediates. The NAD synthetic pathway in H. parainfluenzae differs from the Preiss-Handler pathway and the pyridine nucleotide cycles described in other bacteria.
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PMID:Utilization and metabolism of NAD by Haemophilus parainfluenzae. 325 36

Nutritional factors that influence the growth of Haemophilus somnus were examined, and a defined medium was developed. Optimal growth of H somnus in broth occurred under conditions of maximum aeration. Nutritional components required for or enhanced growth of most H somnus isolates in the defined medium included uracil, D-glucose, isotonic NaCl, Na2HPO4, nicotinamide, flavin mononucleotide, pantothenic acid, pyridoxine, and a variety of salts and amino acids. The defined medium supported optimum growth of 18 of 21 isolates of H somnus from cattle.
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PMID:Development of a defined medium for Haemophilus somnus isolated from cattle. 356 90


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