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At least 19 recordsLinked to original sources
PubMed1990

Degradation of the metal-cyano complex tetracyanonickelate(II) by cyanide-utilizing bacterial isolates.

Ten bacterial isolates capable of growth on tetracyanonickelate(II) [K2[Ni(CN)4]] (TCN) as the sole nitrogen source were isolated from soil, freshwater, and sewage sludge enrichments. Seven of the 10 were identified as pseudomonads, while the remaining 3 were classified as Klebsiella species. A detailed investigation of one isolate, Pseudomonas putida BCN3, revealed a rapid growth rate on TCN (generation time, 2 h), with substrate removal and growth occurring in parallel. In addition to TCN, all isolates were able to utilize KCN, although the latter was significantly more toxic; MICs ranged from 0.2 to 0.8 mM for KCN and greater than or equal to 50 mM for TCN. While growth occurred over a wide range of TCN concentrations (0.25 to 16 mM), degradation was most substantial under growth-limiting conditions and did not occur when ammonia was present. In addition, cells grown on TCN were found to accumulate nickel cyanide [Ni(CN)2] as a major biodegradation product. The results show that bacteria capable of growth on TCN can readily be isolated and that degradation (i) appears to parallel the capacity for growth on KCN, (ii) does not occur in the presence of ammonia, and (iii) proceeds via the formation of Ni(CN)2 as a biological metabolite.

Biodegradation, Environmental↗
PubMed1991

Purification and properties of an organophosphorus acid anhydrase from a halophilic bacterial isolate.

A moderately halophilic bacterial isolate has been found to possess high levels of enzymatic activity against several highly toxic organophosphorus compounds. The predominant enzyme, designated organophosphorus acid anhydrase 2, has been purified 1,000-fold to homogeneity and characterized. The enzyme is a single polypeptide with a molecular weight of 60,000. With diisopropylfluorophosphate as a substrate, the enzyme has optimum activity at pH 8.5 and 50 degrees C, and it is stimulated by manganese and cobalt.

Antibodies, Monoclonal↗
PubMed1987

[Clinical observation of bacterial isolates from urine specimens of outpatients].

Changes of bacterial isolates from urine specimens of outpatients with urinary tract infections (UTI) from 1977 through 1984 were studied. Organisms which were isolated from patients with bacteriuria of over 10(3) bacteria per ml of urine regardless of grade of pyuria were studied. The incidence of UTI, especially that of acute cystitis was decreased during the recent 8 years. E. coli was the most predominant isolate in acute UTI with an isolation frequency of over 70% every year, followed by S. epidermidis nearly every year. Citrobacter spp., Klebsiella spp., P. mirabilis and S. aureus were also isolated steadily every year. Bacterial isolates in acute UTI were generally composed of these six species of bacteria. Although many kinds of bacteria were isolated in chronic UTI, E. coli was the most frequent species with an isolation frequency of 17-37%, followed by E. faecalis except in 1981 and 1982. The tendency of gram-negative rods to increase in acute and chronic UTI was observed except in 1981 and 1982. A slight decrease in sensitivity of E. coli and P. mirabilis against ampicillin (ABPC) and sulbenicillin (SBPC) was observed in acute UTI. In chronic UTI, the tendency of the sensitivity of E. coli against ABPC, SBPC and nalidixic acid to recover and the tendency of the sensitivity of P. aeruginosa against dibekacin to decrease were observed. E. faecalis was estimated to be sensitive to gentamicin, cefazolin, minocycline and fosfomycin. However, unlike those species mentioned above, many strains of E. faecalis showed a positive disc sensitivity to these drugs.

Acute Disease↗
PubMed1977

Influence of hydrostatic pressure on the effects of the heavy metal cations of manganese, copper, cobalt, and nickel on the growth of three deep-sea bacterial isolates.

Increases hydrostatic pressure varied the 72-h growth yield of three bacterial isolates from the deep sea in the presence of heavy metal cations of Mn, Cu, Co, and Ni, depending on the bacterial isolate, the metal cation and its concentration, and the level of hydrostatic pressure. Above atmospheric, hydrostatic pressure was found to have one of the following four effects on the response of culture growth to a heavy metal cation. (i) It could be without effect; (ii) it could enhance inhibition by a metal cation; (iii) it could increase the 72-h growth yield by a metal cation; or (iv) it could protect against a growth inhibitory effect noted at a lower pressure. Possible reasons for these varied responses are discussed.

Bacteria↗
PubMed1990

[Susceptibilities of clinical bacterial isolates to antimicrobial agents. A study mainly focused on imipenem. Research Group for Testing Imipenem Susceptibility on Clinical Isolates].

We investigated susceptibilities of clinical bacterial isolates to imipenem (IPM) and other antimicrobial agents at 459 hospital laboratories throughout Japan from September to December of 1988. In this study, identification and susceptibility testing were performed at each hospital laboratory and the tests were carried out according to the 1-dilution or 3-dilution disc technique in which susceptibilities are classified into 4 grades: , ++, + and -. IPM had significantly high activity against Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus agalactiae, Neisseria gonorrhoeae, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae, Salmonella spp., Citrobacter freundii, Proteus mirabilis, Providencia rettgeri, Acinetobacter calcoaceticus, Moraxella catarrhalis, Alcaligenes spp., Peptococcus spp./Peptostreptococcus spp., Bacteroides fragilis and Bacteroides spp. and should slightly lower activities on coagulase-negative staphylococci (CNS), Enterococcus faecalis, Haemophilus influenzae, Serratia marcescens, Proteus vulgaris, Providencia stuartii and Pseudomonas aeruginosa than on the above mentioned bacteria. In a comparative study on activities of IPM against bacteria from different clinical sources, no remarkable differences were found due to different sources among S. pneumoniae, E. faecalis, H. influenzae, E. coli, K. pneumoniae, E. cloacae, C. freundii, P. mirabilis or A. calcoaceticus, whereas slight differences were found among Staphylococcus aureus, CNS, S. marcescens and P. aeruginosa.

Anti-Bacterial Agents↗
PubMed1978

Growth characteristics of three bacterial isolates from an arctic soil.

Three bacterial isolates, a Pseudomonas sp., a Bacillus sp., and an Arthrobacter sp., commonly isolated from a hummocky sedge-moss meadow at Devon Island, N.W.T., Canada, were selected for further taxonomic characterization and for a study of the effects of temperature and limiting carbon source on growth. Pseudomonas M216 resembled P. putida and Bacillus M153, B. carotarum. Arthrobacter M51 had growth-factor requirements which were more complex than those of any named species of that genus. The temperature ranges of growth indicated that Pseudomonas M216 and Arthrobacter M51 were psychrotrophic while Bacillus M153 was mesophilic. Growth in batch culture at limiting glucose concentrations enabled the calculation of Ks and Y values for each isolate. These were similar to those obtained for other organisms and Pseudomonas M216 and Bacillus M153 showed a high affinity for glucose. The nutritional versatility of Arthrobacter M51 and its ability to grow at low temperatures and the high growth rates and affinity of Pseudomonas M216 for low substrate concentrations may account for their competitive abilities in the natural environment, while the inability of Bacillus M153 to grow at low temperatures may limit its activity in tundra soils.

Arctic Regions↗
PubMed1991

[Susceptibilities of clinical bacterial isolates to antimicrobial agents, 1989. A study mainly focused on imipenem. The Research Group for Testing Imipenem Susceptibilities of Clinical Isolates].

We investigated susceptibilities of clinical bacterial isolates to imipenem (IPM) and other antimicrobial agents at hospital laboratories throughout Japan from September to December of 1989. The susceptibility testing was carried out according to the 1-dilution or 3-dilution disc technique in which susceptibilities are classified into 4 grades: (+++), (++), (+) and (-). IPM showed markedly high in vitro activities against Streptococcus pneumoniae, Neisseria gonorrhoeae, Moraxella catarrhalis, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter freundii, Acinetobacter calcoaceticus, Bacteroides fragilis and had rather strong activities against Enterococcus faecalis, Haemophilus influenzae, Serratia marcescens, Proteus mirabilis, Morganella morganii, Pseudomonas aeruginosa and Achromobacter xylosoxidans, but was less active to Staphylococcus aureus, coagulase-negative staphylococci and Xanthomonas maltophilia. IPM has been found to have activities superior to those of other antibiotics tested against E. faecalis, E. cloacae, C. freundii, S. marcescens, P. aeruginosa and B. fragilis. No antibiotics tested showed good activities against MRSA except minocycline.

Bacteria↗
PubMed1989

Biotyping of bacterial isolates using the yeast killer system.

Forty-four presumptive killer yeasts were tested against bacterial isolates, including rapid-growing gram-positive and gram-negative bacteria, as well as slow-growing bacteria, such as the mycobacteria. A killer system, based on the patterns of bacterial susceptibility to the action of nine selected killer yeasts, was developed for epidemiological purposes. The killer system, previously standardized for yeasts and hyphomycetes, was adapted to the specific growth conditions of the bacterial isolates. The results obtained confirm that susceptibility to the yeast killer phenomenon is widespread among microorganisms unrelated to yeasts and that it could form the basis for a convenient and adaptable biotyping method in microbiological laboratories.

Bacterial Typing Techniques↗
PubMed1979

Fortimicin A: collaborative in vitro susceptibility. Comparison with amikacin and gentamicin against 11,840 clinical bacterial isolates.

The susceptibility of 11,840 clinical bacterial isolates to fortimicin A was determined by agar dilution or broth microdilution methods and compared with their susceptibility to amikacin and gentamicin. In general, the in vitro activity of fortimicin A was essentially the same as that of amikacin. Significant exceptions were the increased effectiveness of fortimicin A against Serratia marcescens and the greater activity of amikacin against Pseudomonas and other nonfermentative gram-negative bacilli. On a weight-for-weight basis, gentamicin showed greater activity than the other two antimicrobial drugs against most species; S. Marcescens was the major exception. However, at concentrations equivalent to achievable nontoxic serum levels, the proportion of isolates inhibited by the three drugs was quite comparable. There were several strains with unusually high resistance to one or more of the tested antibiotics. These usually occurred in one of the six participating institutions and could be traced to specific enzyme-producing or permeability mutants endemic to that particular institution.

Amikacin↗
PubMed1986

An investigation of the in vitro anti-bacterial activity of noxythiolin against 1,000 pathogenic bacterial isolates.

The susceptibility of 1,000 recent bacterial isolates to noxythiolin was determined by the disc susceptibility method. No Gram-positive strains were resistant to this method but 56 (5.6%) of Gram-negative strains gave zones of inhibition of 12 mm diameter or less. The minimum inhibitory concentration (MIC) of the latter were determined by the agar incorporation method. No strains had MIC values greater than 4096 mg/litre. Since concentrations of 50,000 mg/litre can be used for topical treatment, these organisms may be considered susceptible.

Bacteria↗
PubMed1987

Epidemiologic factors affecting antimicrobial resistance of common bacterial isolates.

The pattern of antimicrobial resistance of common bacterial isolates obtained from various groups of patients at a large tertiary-care center was compared with the pattern of resistance seen at a primary-care community hospital. At the tertiary-care center, significant differences in susceptibility were seen between pediatric and adult groups. In the tertiary-care center, the inpatients were more likely than the outpatients to have resistant staphylococcal and enterobacterial strains. Comparison of the overall resistance at the tertiary-care center and the primary-care hospital showed that resistance to cephalosporins, piperacillin, and aminoglycosides was significantly higher at the tertiary-care hospital than at the community hospital. Striking differences were noted in the resistance of nosocomial Enterobacter and Citrobacter isolates. Hospitals should be cautious in extrapolating nationwide data to their particular institutions.

Adolescent↗
PubMed1991

Penicillin amidohydrolase productivity of locally isolated bacterial species.

Penicillin amidohydrolase productivity of four locally isolated bacterial species is described. Organisms were identified as Escherichia coli, Pseudomonas aeruginosa, Sarcina lutea and Bacillus megaterium. Highest enzyme productivity of 3.2 U/mL with a corresponding dry cell mass of 4.5 g/L was recorded from S. lutea.

Bacillus megaterium↗
PubMed1991

Bacterial isolates and drug susceptibility tests at Kaffa Regional Public Health Laboratory, south west Ethiopia.

A two year period bacteriological data was analysed and the frequent bacterial isolates from different clinical specimens included: S. aureus, 25% E. coli, 15%; Proteus spp 14%; Citrobacter-Enterobacter group, 10% coagulase negative Staphylococcus species, 9%; and other miscellaneous bacteria each less than 9%. The majority of the bacterial isolates were resistant to commonly available antimicrobial agents like tetracycline, ampicillin, and chloramphenicol.

Bacteria↗
PubMed1991

Production of trypsin and chymotrypsin inhibitors by oral bacterial isolates.

Using an agar-skim milk gel method, over 300 oral bacterial isolates were tested for their ability to produce trypsin or chymotrypsin inhibitor. Eleven bacterial strains, including seven isolates identified as Bacteroides intermedius, were found to inhibit both proteolytic activities. The inhibitory factors of the 11 bacterial strains could be divided into two categories: i) heat-stable and dialysable, and ii) heat-labile and non-dialysable. The protease inhibitor activity of B. intermedius strains, which belongs to the latter category, was found in a membrane fraction as well as in a membrane-free extract. Furthermore, three strains of B. intermedius showed this inhibitory activity in the culture supernatant. In combination with plasma-derived protease inhibitors, the production of these additional protease inhibitors by oral bacteria could protect the host from tissue degradation.

Adult↗
PubMed1985

Nitrogen utilization in bacterial isolates from the equine cecum.

A total of 114 bacterial isolates were obtained from the cecal contents of two mature cecally fistulated horses on a habitat-simulating medium containing 40% energy-depleted cecal fluid. Of these isolates, 108 were maintained in pure cultures and were tentatively grouped on the basis of cell morphology and physiological characteristics. Gram-negative rods (50.9%), gram-positive rods (22.8%), and gram-positive cocci (21.9%) represented the largest groups isolated from these animals. Fifty isolates were tested for their ability to grow in media containing urea, ammonia, peptones, or amino acids as sole nitrogen sources. None of the isolates had a unique requirement for urea or ammonia since nitrogen derived from peptones, amino acids, or both supported growth as well as did ammonia or urea in a low nitrogen medium. Of the cecal isolates, 18% were able to use urea for growth, and 20.5% were able to grow with ammonia as the sole nitrogen source. All organisms grew in the experimental media containing peptones as the sole nitrogen source. Urease activity was detected in only 2 of 114 isolates tested. The inability of isolates to use urea or ammonia as nitrogen sources may have been a reflection of growth conditions in the habitat-stimulating medium used for isolation, but it could also suggest that many cecal bacteria require nitrogen sources other then ammonia or urea for growth.

Animals↗
PubMed1986

Etiologic significance of bacterial isolates from rams with palpable epididymitis.

Identified and partly identified bacterial isolates were obtained from 48 rams of various breeds that had unilateral or bilateral epididymitis. Most of the animals were approximately 1 year of age; a few were older. Brucella ovis, Actinobacillus spp, Corynebacterium spp, Haemophilus spp, Acinetobacter spp, Escherichia coli, Moraxella spp, Staphylococcus spp, Pasteurella spp, Streptococcus spp, and Chlamydia psittaci were isolated. A vaccine strain of B ovis, isolated species of bacteria, and mixtures of isolates of tissue homogenates containing all isolates except B ovis and C psittaci were inoculated via the mucous membranes of the eyes, nares, and prepuce. Palpable epididymitis was not produced by the inoculations. The vaccine strain of B ovis induced complement-fixation reaction in 11 of 20 rams.

Acinetobacter↗
PubMed1992

Synergism of trimethoprim and ciprofloxacin in vitro against clinical bacterial isolates.

For the first time, the effects of combinations of trimethoprim and a fluoroquinolone (ciprofloxacin) against gram-positive and gram-negative bacterial isolates were evaluated in vitro. Synergism was found in 31% (fractional inhibitory concentration, FIC) and 33% (fractional bactericidal concentration, FBC) of 121 clinical isolates of various bacterial strains, most often in Escherichia coli, staphylococci, and enterococci. Antagonism occurred in 1% (FIC) and 3% (FBC). The combination of trimethoprim and ciprofloxacin merits further evaluation for potential usefulness as a clinical regimen.

Ciprofloxacin↗