Distribution of Aldoxime Dehydratase in Microorganisms

The distribution of phenylacetaldoxime-degrading and pyridine-3-aldoxime-degrading ability was examined with intact cells of 975 microorganisms, including 45 genera of bacteria, 11 genera of actinomyces, 22 genera of yeasts, and 37 genera of fungi, by monitoring the decrease of the aldoximes by high-pressure liquid chromatography. The abilities were found to be widely distributed in bacteria, actinomyces, fungi, and some yeasts: 98 and 107 strains degraded phenylacetaldoxime and pyridine-3-aldoxime, respectively. All of the active strains exhibited not only the aldoxime-dehydration activity to form nitrile but also nitrile-hydrolyzing activity. On the other hand, all of 19 nitrile-degrading microorganisms (13 species, 7 genera) were found to exhibit aldoxime dehydration activity. It is shown that aldoxime dehydratase and nitrile-hydrolyzing activities are widely distributed among 188 aldoxime and 19 nitrile degraders and that the enzymes were induced by aldoximes or nitriles.     

Distribution of aldoxime dehydratase in microorganisms

The distribution of phenylacetaldoxime-degrading and pyridine-3-aldoxime-degrading ability was examined with intact cells of 975 microorganisms, including 45 genera of bacteria, 11 genera of actinomyces, 22 genera of yeasts, and 37 genera of fungi, by monitoring the decrease of the aldoximes by high-pressure liquid chromatography. The abilities were found to be widely distributed in bacteria, actinomyces, fungi, and some yeasts: 98 and 107 strains degraded phenylacetaldoxime and pyridine-3-aldoxime, respectively. All of the active strains exhibited not only the aldoxime-dehydration activity to form nitrile but also nitrile-hydrolyzing activity. On the other hand, all of 19 nitrile-degrading microorganisms (13 species, 7 genera) were found to exhibit aldoxime dehydration activity. It is shown that aldoxime dehydratase and nitrile-hydrolyzing activities are widely distributed among 188 aldoxime and 19 nitrile degraders and that the enzymes were induced by aldoximes or nitriles.     

Groups and sources of yeasts in house dust

House dust contains bacteria, mycelial fungi, microarthropods, and yeasts. The house dust samples collected in 25 apartments in Moscow and the Moscow region were found to contain yeasts belonging to the genera Candida, Cryptococcus, Debaryomyces, Rhodotorula, Sporobolomyces, and Trichosporon. The most frequently encountered microorganisms were typical epiphytic yeasts, such as Cryptococcus diffluens and Rhodotorula mucilaginosa, which are capable of long-term preservation in an inactive state. The direct source of epiphytic yeasts occurring in the house dust might be the indoor plants, which were contaminated with these yeasts, albeit to a lesser degree than outdoor plants. Along with the typical epiphytic yeasts, the house dust contained the opportunistic yeast pathogens Candida catenulata, C. guillermondii, C. haemulonii, C. rugosa, and C. tropicalis, which are known as the causal agents of candidiasis. We failed to reveal any correlation between the abundance of particular yeast species in the house dust, residential characteristics, and the atopic dermatitis of the inhabitants.     

Chemiluminescent assay for detection of viable microorganisms

The redox reaction between quinone and viable microorganisms produces active oxygen species. In this study, the production rates of active oxygen species were determined by a luminol chemiluminescent assay, and the luminescence intensity was found to be proportional to the viable cell number. The high sensitivity of the luminol chemiluminescent assay was achieved with Mo-ethylenediaminetetraacetate complex and menadione or coenzyme Q1. The detectable cell densities of bacteria and yeasts were found to be approximately several thousand colony-forming units (CFU/ml) when assays were performed with a 96-well microplate luminometer. The chemiluminescent assay requires 10 min for incubation of quinone and microorganisms and 2s for photon counting. Single Escherichia coli was detected after 4h of cultivation and centrifugation (5 min x 2). This simple chemiluminescent assay is expected to be useful for the rapid detection of viable bacteria and yeast.     

Studies on Cardiotonic Substances Produced by Microorganisms. (I)

The active substances such as cardiotonics or toxics which were produced in the cultured broths or contained in the mycellia of microorganisms were examined by Ito’s assay method for cardiotonica using the embryonic heart of Japanese killi-fish.

There were some strains obtained from actinomycetes whose cultured broths or methanol mycelial extracts showed these activities, but fewer from moulds, yeasts and bacteria.     

Groups and Sources of Yeasts in House Dust

House dust contains bacteria, mycelial fungi, microarthropods, and yeasts. House dust samples collected in 25 apartments in Moscow and the Moscow region were found to contain yeasts belonging to the genera Candida, Cryptococcus, Debaryomyces, Rhodotorula, Sporobolomyces, and Trichosporon. The most frequently encountered microorganisms were typical epiphytic yeasts, such as Cryptococcus diffluens and Rhodotorula mucilaginosa, which are capable of long-term preservation in an inactive state. The direct source of epiphytic yeasts occurring in the house dust might be indoor plants, which were contaminated with these yeasts, albeit to a lesser degree than outdoor plants. Along with the typical epiphytic yeasts, the house dust contained the opportunistic yeast pathogens Candida catenulata, C. guillermondii, C. haemulonii, C. rugosa, and C. tropicalis, which are known as the causal agents of candidiases. We failed to reveal any correlation between the abundance of particular yeast species in the house dust, residential characteristics, and the atopic dermatitis of the inhabitants.     

Spores of the mycorrhizal fungus <Emphasis Type="Italic">Glomus mosseae</Emphasis> host yeasts that solubilize phosphate and accumulate polyphosphates

The present paper reports the presence of bacteria and yeasts tightly associated with spores of an isolate of Glomus mosseae. Healthy spores were surface disinfected by combining chloramine-T 5%, Tween-40, and cephalexin 2.5 g L⁻¹ (CTCf). Macerates of these spores were incubated on agar media, microorganisms were isolated, and two yeasts were characterized (EndoGm1, EndoGm11). Both yeasts were able to solubilize low-soluble P sources (Ca and Fe phosphates) and accumulate polyphosphates (polyPs). Sequence analysis of 18S ribosomal deoxyribonucleic acid showed that the yeasts belong to the genera Rhodotorula or Rhodosporidium (EndoGm1) and Cryptococcus (EndoGm11). Results from inoculation experiments showed an effect of the spore-associated yeasts on the root growth of rice, suggesting potential tripartite interactions with mycorrhizal fungi and plants.     

Nine-year microflora study of an isolator-maintained immunodeficient child

A male child, maintained in a controlled environment, was monitored each month for bacteria, yeasts, and filamentous fungi recovered from the mouth, nasal passages, feces, and nine body surface sites. Three natural microbial categories became apparent. Incident microorganisms were recovered from within the isolator but did not establish permanent residence. Of the 53 incident types isolated, 20 were filamentous fungi and 4 were yeasts. Some genera, such as Fusobacterium, Lactobacillus, Neisseria, and Rothia, which were commonly found in the reference group, did not become permanent inhabitants. Transient microorganisms were repeatedly recovered but could not be demonstrated within the isolated environment at the end of the study. The loss of only a few of the 19 transient species could be associated with antimicrobial therapy. Permanent microorganisms consisted of Pencillium citrinum and 17 bacterial types, of which alpha-hemolytic streptococci, Staphylococcus edpidermidis subgroups II and V, Micrococcus groups 1 and 2, Clostridium bifermentans, and Propionibacterium acnes were recovered throughout the entire 9 years of the study. The number of CFUs recovered from each sample type was generally not unlike that from the reference group of healthy male adults. Also, the number of different aerobic species recovered from the feces was within the normal range of that of the reference group. In contrast, the number of different species recovered from all other samples was less than that commonly found in the reference group.     

Production of Extracellular l-Asparaginases by Microorganisms

A variety of microorganisms were tested for their extracellular l-asparaginase productivity and it was found that many bacteria, fungi and yeasts are positive for it. Especially some strains in the genera Pseudomonas, Candida and Rhodotorula were able to produce a large amounts of the enzyme. Escherichia coli, however, that contained intracellular enzyme was unable to produce extracellular one. In enzymological properties some differences were noted among these extracellular enzymes. Pseudomonas asparaginase showed glutaminase activity too, but the asparaginases of Candida and Rhodotorula were unable to hydrolyze glutamine. Candida l-asparaginase was most stable to heat-treatment.     

Nine-year microflora study of an isolator-maintained immunodeficient child.

A male child, maintained in a controlled environment, was monitored each month for bacteria, yeasts, and filamentous fungi recovered from the mouth, nasal passages, feces, and nine body surface sites. Three natural microbial categories became apparent. Incident microorganisms were recovered from within the isolator but did not establish permanent residence. Of the 53 incident types isolated, 20 were filamentous fungi and 4 were yeasts. Some genera, such as Fusobacterium, Lactobacillus, Neisseria, and Rothia, which were commonly found in the reference group, did not become permanent inhabitants. Transient microorganisms were repeatedly recovered but could not be demonstrated within the isolated environment at the end of the study. The loss of only a few of the 19 transient species could be associated with antimicrobial therapy. Permanent microorganisms consisted of Pencillium citrinum and 17 bacterial types, of which alpha-hemolytic streptococci, Staphylococcus edpidermidis subgroups II and V, Micrococcus groups 1 and 2, Clostridium bifermentans, and Propionibacterium acnes were recovered throughout the entire 9 years of the study. The number of CFUs recovered from each sample type was generally not unlike that from the reference group of healthy male adults. Also, the number of different aerobic species recovered from the feces was within the normal range of that of the reference group. In contrast, the number of different species recovered from all other samples was less than that commonly found in the reference group.     

Exploring the evolution of multicellularity in Saccharomyces cerevisiae under bacteria environment: An experimental phylogenetics approach

There have been over 25 independent unicellular to multicellular evolutionary transitions, which have been transformational in the complexity of life. All of these transitions likely occurred in communities numerically dominated by unicellular organisms, mostly bacteria. Hence, it is reasonable to expect that bacteria were involved in generating the ecological conditions that promoted the stability and proliferation of the first multicellular forms as protective units. In this study, we addressed this problem by analyzing the occurrence of multicellularity in an experimental phylogeny of yeasts (Sacharomyces cerevisiae) a model organism that is unicellular but can generate multicellular clusters under some conditions. We exposed a single ancestral population to periodic divergences, coevolving with a cocktail of environmental bacteria that were inoculated to the environment of the ancestor, and compared to a control (no bacteria). We quantified culturable microorganisms to the level of genera, finding up to 20 taxa (all bacteria) that competed with the yeasts during diversification. After 600 generations of coevolution, the yeasts produced two types of multicellular clusters: clonal and aggregative. Whereas clonal clusters were present in both treatments, aggregative clusters were only present under the bacteria treatment and showed significant phylogenetic signal. However, clonal clusters showed different properties if bacteria were present as follows: They were more abundant and significantly smaller than in the control. These results indicate that bacteria are important modulators of the occurrence of multicellularity, providing support to the idea that they generated the ecological conditions‐promoting multicellularity.     

Bacteria and yeasts associated with Sirex noctilio

Five genera of bacteria and yeasts commonly occur in the oviposition drills and larval galleries of Sirex noctilio. In exceptional circumstances, some of these microorganisms may be pathogenic while the yeast, Saccharomyces sp., is involved in the production of attractants of the rhyssine parasitoids Rhyssa and Megarhyssa spp. A possible role in larval nutrition is suggested but these microorganisms have no role in the phytotoxic effects of Sirex attack.     

Growth kinetics of microorganisms isolated from Alaskan soil and permafrost in solid media frozen down to -35 degrees C

We developed a procedure to culture microorganisms below freezing point on solid media (cellulose powder or plastic film) with ethanol as the sole carbon source without using artificial antifreezes. Enrichment from soil and permafrost obtained on such frozen solid media contained mainly fungi, and further purification resulted in isolation of basidiomycetous yeasts of the genera Mrakia and Leucosporidium as well as ascomycetous fungi of the genus Geomyces. Contrary to solid frozen media, the enrichment of liquid nutrient solutions at 0 degrees C or supercooled solutions stabilized by glycerol at -1 to -5 degrees C led to the isolation of bacteria representing the genera Polaromonas, Pseudomonas and Arthrobacter. The growth of fungi on ethanol-microcrystalline cellulose media at -8 degrees C was exponential with generation times of 4.6-34 days, while bacteria displayed a linear or progressively declining curvilinear dynamic. At -17 to -0 degrees C the growth of isolates and entire soil community on 14C-ethanol was continuous and characterized by yields of 0.27-0.52 g cell C (g of C-substrate)(-1), similar to growth above the freezing point. The 'state of maintenance,' implying measurable catabolic activity of non-growing cells, was not confirmed. Below -18 to -35 degrees C, the isolated organisms were able to grow only transiently for 3 weeks after cooling with measurable respiratory and biosynthetic (14CO2 uptake) activity. Then metabolic activity declined to zero, and microorganisms entered a state of reversible dormancy.     

Enumeration of petroleum-degrading microorganisms.

A variety of factors, including concentration of oil, antibiotics, dyes, and inoculum washes, were examined to determine their effect on the total counts of microorganisms on oil-containing media. The media found to be best for enumerating petroleum-degrading microorganisms contained 0.5% (vol/vol) oil and 0.003% phenol red, with Fungizone added for isolating bacteria and streptomycin and tetracycline added for isolating yeasts and fungi. Washing the inoculum did not improve recovery of petroleum degraders. Specifically, silica gel-oil medium and a yeast medium are recommended for enumeration of petroleum-degrading bacteria and yeasts and fungi, respectively. It is suggested that counts of petroleum degraders be expressed as percentage of the total population rather than total numbers of petroleum degraders per se. Incubation temperature and presence of oil was found to influence the numbers of petroleum-degrading microorganisms at a given sampling site.     

Survival of microorganisms after drying and storage

Bacteria, yeasts and fungi suspended in a dextran solution were added to ampoules containing strips of filter paper which were dried without vacuum conditions. The ampoules were sealed and stored in the dark at room temperature. Viability counts were made of the original suspension immediately after drying and after storage periods of 3–48 months. Although bacterial cultures of many genera did not show much resistance against dry conditions, bacteria of 13 other genera had survived well or moderately after 4 years of storage. Most of the dried yeast cultures had survived after this period. Of the 16 fungal genera tested, species of 6 genera exhibited growth after 4 years. Results of this study were compared with those of two other preservation methods by which the same microorganisms were used.     

Microbiological studies on amylolytic oriental fermentation starters

Ragi and ragi-like starters were obtained from China, India, Indonesia (Java and Bali), Malaysia, Nepal, Philippines, and Taiwan. These starters have a number of names in each country (murcha, bubod, Chinese yeast). The microorganisms found in 41 samples examined were 3 genera of the Mucorales (Rhizopus, Mucor, Amylomyces), yeasts and bacteria. Except for a few chance contaminants only Mucoraceous fungi were found, and the appearance and growth of colonies of yeasts and bacteria indicate that only 2 or 3 species of each were present. The starters from different countries sold under different names are identical in their flora except that Amylomyces was rarely, if ever, a part of the murcha flora in samples from Nepal. The range in counts were 4x10³ to 2.1×10⁸ bacteria, 4×10³ to 6.1×10⁸ for molds and yeasts, and 3×10³ to 6.1×10⁸ for yeasts alone. The anaerobic count ranged from 3×10² to 1.5×10⁸ and was made up of both yeasts and bacteria. Every sample contained yeast and at least one Mucoraceous mold. Amylomyces was shown to survive long periods of time — as many as 5 years at room temperature resulted in retained amylolytic activity. There was a considerable reduction in isolates of Mucor and Rhizopus with long periods of storage. Chlamydospore germination was seen for the first time in Amylomyces.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.     

Novel bioemulsifiers from microorganisms for use in foods

The main objective of this study was to test a range of microorganisms for production of extracellular, high molecular weight emulsifiers for potential use in foods. A standard emulsification assay developed specifically for assessing food emulsifiers was used to examine 24 extracellular microbial products from bacteria, yeasts and algae. Of the 24 products tested, nine had emulsification ability that was as good as and eight had emulsifying properties that were better than those of the commonly used food emulsifiers gum arabic and carboxymethylcellulose. The eight good producer organisms included the yeasts Candida utilis, Candida valida, Hansenula anomala, Rhodospiridium diobovatum and Rhodotorula graminis, the red alga Porphiridium cruentum, and the bacteria Klebsiella spp. and Acinetobacter calcoaceticus. Of these, C. utilis was selected for further study due to the excellent emulsification properties of its extracellular products and the food-grade status of the organism. Crude preparations of the bioemulsifier from C. utilis exhibited low viscosity and had a carbohydrate content of over 80%. Preliminary trials showed that the bioemulsifier from this organism had potential for use in salad cream.     

Monitoring of microbial degraders in manned space stations

Samples of microorganisms from the surface of constructions of Mir Space Station (Mir SS) were taken and examined after 13 years of operation. The following microorganisms were isolated and identified: 12 fungal species belonging to the genera Penicillium, Aspergillus, Cladosporium, and Aureobasidium; 3 yeast species belonging to the genera Debaryomyces, Candida, and Rhodotorula; and 4 bacterial species belonging to the genera Bacillus, Myxococcus, and Rhodococcus. The predominant species in all samples was Penicillium chrisogenum. It was shown that the fungi isolated could damage polymers and induce corrosion of aluminum-magnesium alloys. We commenced a study of microbial degraders on constructions of the Russian section of the International Space Station (RS ISS). Twenty-six species of fungi, bacteria, yeasts, and actinomycetes, known as active biodegraders, were identified in three sample sets taken at intervals. We founded a collection of microorganisms surviving throughout space flights. This collection can be used to test spacecraft production materials, in order to determine their resistance to biodegradation.     

Biosynthesis of phytoquinones. Incorporation of l-[Me-14C3H]methionine into terpenoid quinones and chromanols in maize shoots

1. Radioactivity from l-[Me-(14)C,(3)H]methionine is incorporated into phylloquinone, plastoquinone, gamma-tocopherol, alpha-tocopherol, alpha-tocopherolquinone and ubiquinone in maize shoots. 2. Comparative studies with other terpenoids (squalene and beta-carotene) and chemical degradation of selected quinones (ubiquinone and plastoquinone) established that all the radioactivity is confined to nuclear methyl substituents. 3. In ubiquinone 76% of the radioactivity is in the methoxyl groups and 24% in the ring C-methyl group. 4. Taking the phytosterols as an internal reference and accepting the atomic ratio of (14)C/(3)H transferred from l-[Me-(14)C,(3)H]methionine to the supernumerary group at C(24) to be 1:2 the ratio of all the quinones and chromanols examined approached 1:3. After allowing for the fact that for plastoquinone, gamma-tocopherol, alpha-tocopherol and alpha-tocopherolquinone one nuclear methyl group is formed from the beta-carbon of tyrosine, these results show that one nuclear C-methyl group for phylloquinone, plastoquinone and gamma-tocopherol, two nuclear methyl groups for alpha-tocopherol and alpha-tocopherolquinone and one nuclear methyl and two methoxyl groups for ubiquinone are formed by the transfer of intact methyl groups from methionine. 5. From a comparison of the incorporation of (14)C radioactivity into these compounds it would appear that the methylation reactions involved in phylloquinone and plastoquinone biosynthesis take place in the chloroplast, whereas those involved with ubiquinone biosynthesis occur else-where within the cell.     

Production of alditols fromd-xylose by yeasts

Production of glycerol, tetritols, pentitols, hexitols and heptitols was tested with 193 strains of yeasts and yeast-like microorganisms belonging to 13 genera. According to the production of alditols, the yeast species were divided into four groups. The largest group consisted of pentitol-producing yeasts. Only few species produced glycerol, tetritol and hexitol. Production of heptitols was found mainly in sporulating yeasts. Translated by Č. Novotny