摘要:

The respiration ofCandida lipolyticaonn-tetradecane is decreased in the presence of bentonite. This inhibition is less pronounced by the introduction of hydrophobic chains on the bentonite. Oxygen demand of resting cells varies with the length of hydrophobic chains. In fermentor, addition of adsorbant does not stimulate growth, but assimilation ofn-tetradecane is enhanced with certain concentrations of the adsorbant. On glucose, addition of hydrophobic chains on the adsorbant does not change the effects of bentonite on exogenous respiration and substrate assimilation.

ISSN:0008-4166    

DOI:10.1139/m76-157

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Ten different group A streptococcal M-protein preparations purified by trichloroacetic acid precipitation and three M-protein preparations purified by cellulose chromatography were examined by SDS and polyacrylamide gel electrophoresis, and analyzed for amino acid composition and N-terminal amino acids. Fingerprinting (both tryptic and chymotryptic) was performed on the cellulose-purified preparations of M1, M12, and M29proteins which showed these proteins to be structurally related. Trypsin produced maps with 37 to 42 peptides, whereas chymotrypsin digestion resulted in 8 to 12 peptides, depending on the M-type. Sequencing was performed on the M12protein and tentative identification of nine N-terminal amino acids was made. Molecular weights of the cellulose and TCA-purified M-proteins were determined by SDS gel electrophoresis and chromatography on G-200 Sephadex, with comparable results, indicating molecular size of at least 23 000. The amino acid analyses of the 10 TCA-purified proteins followed the patterns established for M-proteins, with high concentrations of lysine, aspartic acid, glutamic acid, alanine, and leucine. All 10 proteins hadL-alanine as their N-terminal amino acid. Evidence for a one way cross-reaction between type 1 and type 29 streptococci was also found.

ISSN:0008-4166    

DOI:10.1139/m76-158

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

The citric acid fermentation byAspergillus nigeris divided into two consecutive phases, a growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they produce citrate but do not proliferate, or else do so at a much reduced rate. When studied in a low sucrose (0.4–0.8%) minimal salts medium the growth-accumulation alternative was controlled by the concentration of zinc: high zinc (about 1–2 μM) maintained growth phase, while at low zinc (below 1 μM) growth became limited by zinc deficiency and the cultures passed into accumulating phase. Addition of zinc to accumulating cultures resulted in their reversion to growth phase. Iron, manganese, and calcium at concentrations as high as 5–10 μMhad no influence on either growth or citrate accumulation. These results suggest that zinc plays a role in the regulation of growth and citric acid accumulation.

ISSN:0008-4166    

DOI:10.1139/m76-159

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

The citric acid fermentation byAspergillus nigeris divided into two consecutive phases, growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they excrete citrate but do not proliferate. The phase alternative was controlled by the concentration of zinc: high zinc (2 μM) maintained growth phase, and a zinc 'deficiency apparently signaled the transition to the accumulating phase. Cyclic AMP affected the rates of growth and acidogenesis when added to cultures growing at low but not at high zinc: that is, cAMP did not induce the phase transition, zinc deficiency did. Cyclic AMP enhanced growth early in the fermentation, but at later stages the response of the mycelia to cAMP changed, and then cAMP inhibited growth. When citrate eventually began to accumulate cAMP augmented its synthesis. The growth and acidogenic responses were quite specific to cAMP, and were sensitive to concentrations of about 1 μM. Cyclic AMP also either promoted or retarded the appearance of an unidentified yellow pigment. It is proposed that the growth and accumulating phases are distinct differentiated states, at least with respect to cAMP metabolism.

ISSN:0008-4166    

DOI:10.1139/m76-160

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Torula thermophilaproduced typical chlamydospores either as intercalary chains within prostrate hyphae or as terminal swellings on short, lateral, hyphal branches. Mature chlamydospores were spherical, dark brown, smooth-surfaced structures with thick, single-layered cell walls (= secondary wall layer) usually differentiated into an outer electron-dense zone and an inner electron-transparent zone. Disarticulation and spore release occurred after the disintegration of the original hyphal wall.The thallospores ofT.thermophilaarise in a manner different from the blastospores produced by other species ofTorulaand are structurally more closely related to the spores produced byHumicola insolens. However until further work has been completed on spore development in theTorulu-Humicolacomplex of fungi the nameT.thermophilais retained.

ISSN:0008-4166    

DOI:10.1139/m76-161

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Instillation of the goat's mammary gland withNeisseria gonorrhoeaecolony type Tl has elicited an antibody response in the goat milk serum (GMS). Purification, and characterization of the GMS by gel filtration, electrophoresis, immunodiffusion, analytical ultracentrifugation. And serological analyses demonstrated that the active immune component was mainly in the IgA and IgG fractions (F2 and F3) of GMS.

ISSN:0008-4166    

DOI:10.1139/m76-162

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Results from analyses of β-glucosidase (EC 3.2.1.21) and phosphatase (EC3.1.3.1; EC 3.1.3.2) activities indicated that presence of aTrichodermaisolate reduced development ofPhytophthora cinnamomi. It was also observed thatP.cinnamomiwas more competitive in coinoculated cultures than in cultures whereTrichodermawas added on day 3. Analysis of trehalase (EC 3.2.1.28) activity indicated thatTrichodermaeither utilized portions of theP.cinnamomimycelium as substrate or the action ofP.cinnamomireleased additional nutrients not normally available toTrichoderma. The strongerTrichodermaisolate wasT.harzianum.

ISSN:0008-4166    

DOI:10.1139/m76-163

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

Replication of a subarctic Bunyavirus, California encephalitis (snowshoe hare subtype), was detected in salivary glands and thoraces of wild-caughtAedes communismosquitoes from the Yukon Territory, after intrathoracic inoculation with 0.1 to 100 mouse LD50virus, and incubation for 7 to 21 days throughout their viable temperature range of 0 to 23 °C. Immunoperoxidase staining confirmed that viral replication occurred in the cytoplasm of acinar cells of salivary glands, both by light microscopy and electron microscopy. Replication of another subarctic Bunyavirus. Northway, and a subtropical Flavivirus, Murray Valley encephalitis, was also demonstrated by infectivity titrations and immunoperoxidase reactions in salivary glands ofA.communisincubated at 0, 13, and 23 °C for 7 to 21 days.

ISSN:0008-4166    

DOI:10.1139/m76-164

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

A biologically active metabolite was found in crude extracts of an unidentified species ofPhomopsisisolated from weevil-damaged pecans. Purified metabolite was toxic to day-old cockerels, with an LD50of 12.5 mg/kg, and was markedly inhibitory to growth and floral development of tobacco plants at concentrations of 10−2to 10−4 M. IR and1H-nmr spectra indicated an alkylphenyl moiety with a single nitrogen atom present as a secondary amide: and acetate ester, OH, CH3, and a trans-double bond function. Elemental and high-resolution mass-spectral analysis indicated a formula of C30H39NO5and a molecular weight of 493.2886. The metabolite was identified as cytochalasin H.

ISSN:0008-4166    

DOI:10.1139/m76-165

出版商:NRC Research Press    

年代:1976

数据来源: NRC

摘要:

There are indications that the fungus enzymatically degrades the cuticle and epidermal cell wall. The epidermal cells and to a lesser degree the palisade mesophyll cells beneath a sporulating lesion (susceptible reaction) are killed or seriously disrupted. Various stages of conidiogenesis, including development of the primary conidium, were observed. A conidium is delimited by a two-layered transverse septum. Before conidium secession, a new two-layered inner wall is laid down around the entire conidiogenous cell adjacent to the plasmalemma. The apical region of the new inner wall proliferates beyond the annellation scar left by the seceded conidium and eventually produces another conidium.

ISSN:0008-4166    

DOI:10.1139/m76-166

出版商:NRC Research Press    

年代:1976

数据来源: NRC