摘要:

Growth responses of oligotrophic bacteria to substrate concentrations have been investigated in comparison with those of heterotrophic bacteria. The results suggested that oligotrophs were the group which could grow and produce a perceptible turbidity in the media containing less than 10 mg peptone C/L of medium.Taxonomic studies indicated that the most abundant group in the oligotrophic bacterial flora was consistent with that in the heterotrophic bacterial flora at each sampling station. However, the relative proportion of pseudomonads in the oligotrophs was higher than that in the heterotrophs (at stations H-24, H-28, H-29, Ab-1, Ab-2, and O-4), while the relative proportion ofVibrioin the former was lower than that in the latter (at stations H-24, H-28, H-29, O-4, and O-9).

ISSN:0008-4166    

DOI:10.1139/m80-138

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

Plant tissue extracts prepared from corn, periwinkle, celery, and lettuce contain substance(s) which are inhibitory for spiroplasma growth in culture media. The inhibition titer, measured as the highest dilution of plant extracts which block spiroplasma growth, is inversely proportional to the spiroplasma concentration used for testing. At a concentration of 104 cells/mL, the growth of four spiroplasma isolates investigated (corn stunt spiroplasma,Spiroplasma citri, honey bee spiroplasma, and Bermuda grass (Cynodon dactylon) spiroplasma) was suppressed by the addition of corn and periwinkle extracts up to dilutions of 1/160 and 1/1280, respectively. Spiroplasmas remained viable in extract-supplemented media for at least 5 days and continued to multiply shortly after the plant extract was removed. These results suggest that (1) the inhibitory action of plant extracts is spiroplasmastatic, and (2) inhibitory factors may temporarily bind to cytoplasmic membrane and subsequently suppress the process of cell replication. The anti-mycoplasma activity was greatly reduced when the extract was placed in boiling water for 10 min or at 37 °C for 5 days. No loss of activity was detected when the extract was kept at −20 or 4 °C for 5 days.

ISSN:0008-4166    

DOI:10.1139/m80-139

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

When examined in an amino acid supplemented inorganic salts – glucose medium, the morphological development ofCandida albicans5865 is inhibited or delayed by several drugs common to cancer chemotherapy protocols. Yeast phase growth is inhibited by actinomycin D (100 μg/mL), bleomycin (500 μg/mL), 5-fluorouracil (1000 μg/mL), and hydroxyurea (1000 μg/mL). Germ tube formation was also inhibited by actinomycin D (100 μg/mL), and vincristine (100 μg/mL), doxorubicin and bleomycin (each at 500 μg/mL), and 5-fluorouracil, cyclohexamide, hydroxyurea, and vinblastine at 1000 μg/mL, respectively. Following a 3-h exposure to the above drugs supplemented with sublethal concentrations of amphotericin B (AMB), yeast germination and chlamydospore formation were delayed 60–96 h. Culturing yeasts for 24 h in the presence of both AMB and actinomycin D resulted in a 90% loss in viability. Two antimetabolites not common to chemotherapeutic protocols also showed fungistatic and fungicidal activity. At 24 h, pentamidine isethionate (100 μg/mL) alone had a 90% kill rate which increased to greater than 99.99% when combined with AMB. A cyclic hydroxaneic acid, 7-chloro-3,4-dihydro-1-hydroxycarbostyril (7-Cl ADHC), demonstrated the lowest minimum germ tube inhibitory concentration (1 μg/mL). A 90% kill rate was obtained after culturing yeasts for 24 h in 7-Cl ADHC (100 μg/mL) supplemented with AMB.

ISSN:0008-4166    

DOI:10.1139/m80-140

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

A lipopolysaccharide (LPS) was isolated by hot phenol–water extraction from phase IICoxiella burnetii. The LPS was isolated from organisms that had a history of 95 serial yolk sac passages and others that were cloned. The chemical composition of the LPS was partially determined and compared with that of LPS previously isolated from phase I organisms. Most of the sugars present in phase I LPS were detected in phase II LPS; however, there were some quantitative and qualitative differences. The fatty acid profiles of phase I and II LPS were identical. The amount of LPS extracted from phase II organisms was aboutthe amount extracted from phase IC.burnetii. Limulus lysate gelation was observed with subnanogram amounts of both phase I and II LPS. In complement fixation tests, both LPSs reacted only with antisera containing antibodies versus phase I antigen. Ouchterlony immunodiffusion tests demonstrated immunological identity of the two LPSs.

ISSN:0008-4166    

DOI:10.1139/m80-141

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

Municipal water samples were analyzed by membrane filter (MF) procedures for total coliforms, "background" counts, and 24-and 48-h, 35 °C plate counts. Presence–absence (P–A) tests were done on the samples for total coliforms and other indicator bacteria. The frequency of detection of indicator organisms by P–A tests was better than twice that recovered by MF analyses. When the 24-h plate count data were grouped into counting ranges of 0, 1–100, 101–1000, and > 1000, a marked inhibition effect was observed with total coliform MF recoveries on samples producing plate counts > 1000/mL. When the "background" and 48-h plate count results were placed in the corresponding counting ranges, inhibition of indicator organisms in the total coliform MF analyses was not observed. No inhibition effect was observed in the recovery of indicator organisms by P–A tests at any of the counting range levels. The presence of an apparent inhibition effect by high numbers of bacteria in a sample was shown to be influenced by the incubation period and type of count parameter, as well as the isolation technique for detection of indicator organisms.

ISSN:0008-4166    

DOI:10.1139/m80-142

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

Extracellular alkaline phosphatase produced by a marinePseudomonaswas purified to electrophoretic homogeneity. The molecular weight of the enzyme was estimated to be 100 000. The enzyme had maximal activity at pH 11.5. The enzyme was completely inhibited by 1 mMEDTA. However, divalent cations reversed the enzyme inhibition and their order of effectiveness on the reaction was Zn2+ > Ca2+ > Mn2+ > Mg2+ > Sr2+ > Co2+. The enzyme activity was affected by the species of anion whose order of effectiveness was demonstrated to follow the lyotrophic series, Cl− > Br− > NO3−> ClO4− > SCN−. The activity of phosphatase was accelerated linearly by increased pressure until up to 1000 atm (1 atm = 101.325 kPa), and the enzyme activity at 1000 atm was 3.2 times higher than that at 1 atm.

ISSN:0008-4166    

DOI:10.1139/m80-143

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

One hundred and fifty-six strains of bacteria representing 12 genera were tested for augmented haemolysis in the presence of an alpha-toxin-producing strain ofClostridium perfringens. Synergistic haemolysis was produced byAeromonas hydrophila,Acinetobacter calcoaceticus, Serratia marcescens.Staphylococcus aureus, andStaphylococcus epidermidis. The pattern of synergistic haemolysis byS.ureusdiffered from that observed withS.epidermidis, although they both correlated with delta-lysin production. In the case ofA.hydrophila,A.calcoaceticus, andS.marcescens, lipase production correlated with augmented haemolysis. Synergistic haemolysis by all strains tested was inhibited by clostridial antitoxin.

ISSN:0008-4166    

DOI:10.1139/m80-144

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

(+)-p-Chloroamphetamine was readilyN-conjugated byMycobacterium smegmatisand the products obtained were identified by gas–liquid chromatography and mass spectrometry. Formation of theN-conjugation products was dependent upon the history of the culture. Revitalized lyophilates mediated formation of two acetoin derivedp-chloroamphetamineN-conjugates, the Schiff base 4-chloro-α-methyl-N-(1-methylacetonylidine)benzeneethanamine and 4-chloro-α-methyl-N-(1-methylacetonyl)benzeneethanamine. After several subcultures, these products were no longer detected andN-acetyl-p-chloroamphetamine was the only metabolite detected.Mycobacterium smegmatismetabolism of amphetamine was also studied. The metabolic products were analogous to those obtained fromp-chloroamphetamine.

ISSN:0008-4166    

DOI:10.1139/m80-145

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

The presence of ab-type cytochrome inNitrobacter agiliswas demonstrated by its isolation in DEAE-cellulose chromatography and the pyridine protohemochrome derivative. Thisb-type cytochrome was autoxidizable and reacted with NO2−and CO.

ISSN:0008-4166    

DOI:10.1139/m80-146

出版商:NRC Research Press    

年代:1980

数据来源: NRC

摘要:

Isoelectric focusing of the slime glycolipoprotein of a gentamicin-sensitivePseudomonas aeruginosastrain showed the presence of four protein bands at a pH range of 5.45–6. Two additional protein bands at about pH 5.62 and pH 5.3 appeared in the slime glycolipoprotein of a laboratory-induced gentamicin-resistant variant.

ISSN:0008-4166    

DOI:10.1139/m80-147

出版商:NRC Research Press    

年代:1980

数据来源: NRC