The fine structure of PL-1 phage active against Lactobacillus casei ATCC 27092 was investigated by negative staining and the rotation technique. The phage had an isometric hexagonal head, about 60nm in diameter and a flexible and presumably non-contractile tail about 280nm long and 12nm wide. The tail had a terminal appendage appearing as a small plate with prongs to which was attached a short filament. Periodic cross-striations with about 60 turns were observed along the tail axis. Ultrasonic treatment of the phages produced a number of doughnut-shaped particles lying end-on in addition to the tail fragments disrupted to various degrees. Rotation prints of the doughnut-shaped particles showed that they were composed of six morphological subunits surrounding the central hole of about 5nm diameter. It appeared plausible that the tail tube consists of serially connected morphological subunits forming such doughnut-shaped particles.
The quinone system was investigated in sixty-three strains of thirty-five Pseudomonas species, the ubiquinone system being found in all the strains tested. Three systems of Q-8, Q-9, and Q-10 were recognized. Ubiquinone-8 (Q-8) was found in the strains of Pseudomonas acidovorans, "P. cepacia, " "P. cruciviae, " "P. desmolytica, " P. iners, P. flava, P. maltophilia, P. palleronii, P. pictorum, P. pseudoflava, "P. putrefaciens" ("Alteromonasputrefaciens"), "P. rubescens" ("A. putrefaciens"), P. testosteroni, and "Comarnonas terrigena"; Q-9 in those of P. aeruginosa, P. alcaligenes, P. aureofaciens, P. azotoformans, P. clilororaphis, P. fluorescens, P. fulva, "P. lacunogenes, " P. mendocina, P. mucidolens, P. nitroreducens, "P. ochracea, " "P. ovalis, " P, putida, P. straminea, P. stutzeri, and P. taetrolens; and Q-10 in those of P. diminuta, P. vesicularis, and P. paucimobilis. The taxonomic significance of the ubiquinone systems in the genus Pseudomonas was discussed.
When cells of Selenomonas ruminantium were grown in glucose medium containing valerate, a required growth factor, and imidazole, an inhibitor of α-oxidation, they showed abnormally elongated morphology. A small amount of caproate added to the culture medium resulted in recovery from abnormal to normal cell morphology. Therefore, the abnormal shape of the cells arises from deficiency in even-numbered fatty acids. When (1-14C) caproate was added to the culture deficient in even-numbered fatty acids, radioactivity was mainly incorporated into the phospholipid fraction. Approximately three-times-higher radioactivity was detected in plasmalogen phospholipids than in diacyl phospholipids. Specific radioactivities of fatty acids and aldehydes from plasmalogens were higher than those from any other lipid fractions. Fatty acid and aldehyde analysis revealed that radioactivity was incorporated exclusively into long chain even-numbered fatty acids and aldehydes. It was concluded that even-numbered fatty acids and aldehydes are especially important as constituents of plasmalogen phospholipids.
Protoheme IX is the only heme type present in Vitreoscilla, an obligate aerobe of the Beggiatoaceae family. Previous work showed that the heme content of Vitreoscilla cells was very dependent on growth conditions and that cells with high heme content also had a higher respiratory rate and a higher concentration of cytochrome o, the terminal oxidase. Experiments reported here showed that oxygen exerts a primary control on the heme content of Vitreoscilla and that the concentration of the peptone-yeast extract-acetate medium (PYA) was also important. There was an optimum shaking rate at each PYA concentration for maximum heme content and an optimum PYA concentration for each shaking rate. The atmospheric oxygen concentration of the shaking growth medium remained at 100% saturation and then began a rapid decline (t1/2 ca. 1hr) to less than 10% saturation. The time at which this decline began depended on both the PYA concentration and shaking rate at a fixed inoculum. The heme content of the cells increased over 50 fold as the oxygen concentration in the medium decreased during culture. Cells with a sub-maximal heme content exposed for two hr to 1) anaerobic conditions showed a 15% decrease in heme content; 2) 50% atmospheric oxygen, a 26% increase in heme content; 3) 100% atmospheric oxygen, an 80% decrease in heme content. The results show that the optimal oxygen concentration for maximum heme content in Vitreoscilla is relatively low, probably less than 10% atmospheric.
Ultrastructural examinations and biochemical characterizations were carried out on "Miyazaki" strains of sulfate-reducing bacteria, the biochemistry of which has been extensively studied by Japanese scientists, the identification of which, however, has not yet been done satisfactorily. Miyazaki strains, MK, MF, and MY, were all strictly anaerobic, had a single polar flagellum, and contained desulfoviridin and cytochrome c3. Cells of strain MK were typical comma-shaped, short, curved rods (0.5× 1.5-2μm), while cells of strains MF and MY were longer (2-5μm) and were either curved, sigmoid, or spiral. Occasionally the "Y-shape" or blebbing of the cells was observed among cells of MF and MY. The shorter blebs usually had a single flagellum. Carbon sources, buoyant density of DNA, and electrophoretic mobilities of desulfoviridin, ATP sulfurylase, and adenosine phosphosulfate reductase were also determined. Although cells of strains MF and MY were clearly distinguished from other cells of Desulfovibrio spp. in morphology, all three strains were identified as Desulfovibrio vulgaris.
The presence or absence of metulae, the color of conidial heads, and the pink coloring of the conidia on Czapek agar slant cultures containing 0.05% anisaldehyde can be possibly regarded as criteria and key characters by which to distinguish three taxa, i.e., Aspergillus sojae Sakaguchi et Yamada ex Murakami, A. parasiticus Speare, and A. toxicarius Murakami. One (strain RIB 4018) of the A. toxicarius strains, producing no pink conidia, is now placed in A. parasiticus on the basis of the dark green color of conidial heads in age. A revised synoptic key is provided for the identification of the yellow-green Aspergilli which produce roughened to echinulate conidia.
Strain B-206 is a new facultative anaerobe, non flagellated, gram negative rod, able to grow on 4-chlorobiphenyl (4CB) and to degrade it. When this strain was grown on 4CB as sole growth substrate, two types of cultures were obtained; either the culture became pink or yellow with the formation of a black pigment. The cultures turning yellow were the more active ones and they were obtained with a large inoculum size or low oxygen tension. 4-Chlorobenzoic acid (4CBA) was detected in both pink and yellow cultures but in much higher concentration in yellow cultures. This compound appeared to be the ultimate metabolite of 4CB in both types of growth since strain B-206 could not grow or degrade 4CBA and that the concentration of 4CBA did not decrease even after the appearance of the yellow compounds. The presence of 4CBA and yellow compounds that differs spectrophotometrically at acid and basic pHs suggest that 4CB is degraded via a meta cleavage between the 1 and 2 position. The absence of any other metabolites than a pink pigment and 4CBA in the pink cultures provides no evidence that in this type of culture there would be some other mechanism of cleavage of the biphenyl molecule. In the yellow culture type, there was also formation of a black pigment. This pigment, like the pink compound, possessed all the characteristics of the phenolic type pigments. Strain B-206 could also grow on biphenyl, 3-chlorobiphenyl, 2-chlorobiphenyl, benzoic acid but it was unable to grow on any of the monochlorinated benzoic acids. Although this strain could not grow on Aroclor 1254, we have evidence that it is partially transformed by this strain.
The mechanism of electric-current generation by Escherichia coli IAM 1016 and the effect of an anion-exchange resin on the amount of the current were investigated by using the electrode system developed by MATSUNAGA et al. (1). The current was increased by addition of succinic acid or glucose, and the increased current was diminished by arsenite. Rotenone and antimycin A3, inhibitors of the respiratory chain, increased the current at lower concentrations and decreased it at higher. These results indicate that the current primarily results from respiratory activity, and that the source of electrons transferred to the electrode is located along the respiratory process. The current was diminished by addition of the resin. This result suggests that electrons can be transferred from cells to resin as well as to the electrode. The transfer of electrons to the resin changed the rate of glucose uptake and enhanced the respiratory activity of the organism.
The growth of Lactobacillus vaccinostercus on hexose as a sole energy source varies from no growth to slow, poor growth. The poor growth of L. vaccinostercus on glucose as a sole energy source was extensively studied. It was demonstrated that potential electron acceptors, i.e., pyruvate, acetoin, and acetone are required for good growth on glucose medium. The products of hexose fermentation were constantly equimolar quantities of lactate, ethanol, and CO2 even in the presence of these potential electron acceptors; it seems that the latter are utilized for electron transfer of the anabolic reaction rather than that of the catabolic tion. Good growth on pentose or gluconate as a sole energy source was reacfound without these potential electron acceptors. Their reduction by NADH2 or NADPH2 was demonstrated in the cell-free extracts of L. vaccinostercus from glucose medium, but the cell-free extracts from a pentose medium either did not catalyze, or only slightly so, this reduction with the exception of pyruvate. NADP-dependent reduction activities of acetoin and acetone were especially highly induced by the addition of these substances to glucose medium. From these results, the slow and poor growth of L. vaccinostercus was presumed to be due to the distortion of electron transfer in the growing cell.
Edited and published by : Applied Microbiology, Molecular and Cellular Biosciences Research Foundation/Center for Academic Publications Japan Produced and listed by : TERRAPUB, Center for Academic Publications Japan/Shobi Printing Co., Ltd. (-Vol.60,No12), Center for Academic Publications Japan/InternationalAcademic Printing Co., Ltd.(-Vol.54,No1)