Isolation and characterization of a bluegill-degrading microorganism, and analysis of the root hair-promoting effect of the degraded products

Bluegill-degrading bacteria were isolated from various environmental sources. Brevibacillus sp. BGM1 degraded bluegill efficiently at 50 degrees C, and its culture supernatant showed the highest peptide and amino acid concentrations as trichloroacetic acid (TCA) soluble fraction (ASF) (10.7 mg/ml) of all supernatants obtained with bluegill as a substrate. Strain BGM1 secreted a protease(s) into the medium, and the concentration of peptides and amino acids gradually increased. The fertile effect of the degraded bluegill products (DGP) on Brassica rapa was also investigated. The root hair density of B. rapa grown with DGP at a concentration of 30 mug peptides and amino acids/ml was about 1.7 times higher than when grown with the same concentration of undegraded bluegill. DGP was shown to increase root hair numbers and adventitious root formation. The results of this study suggest that a specific peptide(s) for promotion of root hair is produced from the order Perciformes with a protease(s) from BGM1.     

Isolation and characterization of acid- and Al-tolerant microorganisms

Acid- and aluminum (Al)-tolerant microorganisms were isolated from tea fields, from which six strains were selected and identified as Cryptococcus humicola, Rhodotorula glutinis, Aspergillus flavus Link, Penicillium sp., Penicillium janthinellum Biourge and Trichoderma asperellum. They were tolerant to Al up to 100-200 mM and could grow at low pH, 2.5-2.2. In a glucose medium (pH 3.5) the pH of the spent medium decreased to below 3.0. The toxic inorganic monomeric Al in the spent medium decreased with three strains (A. flavus F-6b, Penicillium sp. F-8b and P. janthinellum F-13), but the total Al remained constant for all strains. In a soil extract medium (pH 3.5), the pH of the spent medium of all strains increased to around 6.0-7. 2 and total Al in the spent medium was removed by precipitation due to pH increase. Thus, different tolerance mechanisms were suggested in glucose and soil extract media.     

Phylogenetic and physiological characterization of organic waste-degrading bacterial communities

One of the greatest challenges in contemporary society is to reduce and treat household solid waste. The choice of inoculum to be used for start-up in reactors that degrade organic waste is critical to the success of organic waste treatment. In this study, the functional diversity, phylogenetic identification, and biogas production of bacterial communities from six inoculum sources were investigated. We used BIOLOG EcoPlates to evaluate the metabolic abilities of the bacterial communities, followed 16S rRNA gene sequence analysis to determine the phylogenetic affiliation of the bacteria responsible for carbon consumption. We observed great diversity in the physiological profiles. Of the six inocula tested, the sludge from an upflow anaerobic sludge blanket reactor (SRU) contained the most diverse, metabolically versatile microbiota and was characterized by the highest level of biogas production. By contrast, the sludge of the anaerobic lagoon (SAL) showed the worst performance in BIOLOG EcoPlates assays, but it exhibited the most diversity and generated the second largest amount of biogas. The bacterial isolates retrieved from BIOLOG EcoPlates were characterized as aerobic and/or facultative anaerobic, and were mainly Gram-negative. Phylogenetic analysis revealed that the isolates belonged to three major phyla: Proteobacteria, Firmicutes and Actinobacteria, represented by 33 genera. Proteobacteria exhibited the most diversity. The distribution of the bacterial genera differed considerably among the six inocula. Pseudomonas and Bacillus, which are able to degrade a wide range of proteins and carbohydrates, predominated in five of the six inocula. Analysis of the bacterial communities in this study indicates that both SRU and SAL microbiota are candidates for start-up inocula in anaerobic reactors. These start-up inocula must be studied further in order to identify their practical applications in degrading organic waste.     

Organic and inorganic fertilizer effects on a degraded Patagonian rangeland

The forest-steppe ecotone in NW Patagonia is a semiarid ecosystem affected by natural and anthropogenic fires, and overgrazing by sheep. Following a wild fire in the driest portion of this ecotone, a 3-year study was conducted to assess the impacts of a single application of inorganic and organic fertilizers on soil and vegetation recovery. Organic fertilizers were composts derived from biosolids and municipal solid wastes. Six treatments were evaluated: screened and unscreened biosolids compost and municipal solid wastes compost (40 Mg ha^?1), inorganic fertilizer (100 kg N and 35 kg P ha^?1), and no application. Soils were chemically characterized, and soil microbial activity was assessed as potential respiration and N-mineralization. Vegetation responses included plant cover, composition, phytomass, and N resorption prior to abscission, and leaf litter quality of the dominant species. Organic fertilizers increased soil organic matter, nutrients and microbial activity. Plant cover and aboveground phytomass, dominated by the native perennial tussock grass Poa ligularis, showed a higher increase with inorganic than with organic fertilization. While vegetation responded more to inorganic fertilizer, due to its higher initial pulse of available N, organic fertilizers had a positive impact on soil chemical and biological properties.     

Proteins of soybean seeds: I. Isolation and characterization of the major components

Soybean (Glycine max) storage proteins were characterized by sedimentation and by polyacrylamide gel electrophoresis under dissociating (8 m urea) and nondissociating conditions. Three sedimenting classes of proteins were found, with sedimentation coefficients of 2.2S, 7.5S, and 11.8S. The coefficients were related to the bands obtained by electrophoretic separation. The results support the idea that relatively few proteins make up the bulk of the seed protein.     

Studies on soybean trypsin inhibitors. X. Isolation and partial characterization of four soybean double-headed proteinase inhibitors

Four Bowman-Birk type double-headed inhibitors (B, C-II, D-II, and E-I) were isolated from soybeans. Inhibitor B was different from Bowman-Birk inhibitor only in chromatographic behavior. One mole of C-II inhibited one mole each of bovine trypsin and bovine alpha-chymotrypsin, probably at the same site, and porcine elastase at another reactive site. In the ordinary assay system D-II and E-I inhibited only trypsin activity at a non-stoichiometric inhibitor-enzyme ratio of 1:1.4, and the complexes had rather high dissociation constants. These inhibitors were all inactive toward subtilisin BPN'.     

Isolation and characterization of organelles from soybean suspension cultures

Whole homogenates from cells of Glycine max grown in suspension culture were centrifuged on linear sucrose gradients. Assays for marker enzymes showed that distinct peaks enriched in particular organelles were separated as follows: endoplasmic reticulum (density 1.10 g/cm³, NADH-cytochrome-c reductase), Golgi membranes (density 1.12 g/cm³, inosine diphosphatase), mitochondria (density 1.18—1.19 g/cm³, fumarase, cytochrome oxidase) and microbodies (density 1.21—1.23 g/cm³, catalase). In cells which had ceased to grow (stationary phase) only a single symmetrical catalase peak at density 1.23 g/cm³ was observed on the sucrose gradient. During the phase of cell division and expansion a minor particulate catalase component of lighter density was present; its possible significance is discussed.     

Biodegradation of Leonardite by an Alkali-producing bacterial community and characterization of the degraded products

In this study, three bacterial communities were obtained from 12 Leonardite samples with the aim of identifying a clean, effective, and economic technique for the dissolution of Leonardite, a type of low-grade coal, in the production of humic acid (HA). The biodegradation ability and characteristics of the degraded products of the most effective bacterial community (MCSL-2), which degraded 50% of the Leonardite within 21 days, were further investigated. Analyses of elemental composition, ¹³C NMR, and Fourier transform infrared revealed that the contents of C, O, and aliphatic carbon were similar in biodegraded humic acid (bHA) and chemically (alkali) extracted humic acid (cHA). However, the N and carboxyl carbon contents of bHA was higher than that of cHA. Furthermore, a positive correlation was identified between the degradation efficiency and the increasing pH of the culture medium, while increases of manganese peroxidase and esterase activities were also observed. These data demonstrated that both alkali production and enzyme reactions were involved in Leonardite solubilization by MCSL-2, although the former mechanism predominated. No fungus was observed by microscopy. Only four bacterial phylotypes were recognized, and Bacillus licheniformis-related bacteria were identified as the main group in MCSL-2 by analysis of amplified 16S rRNA genes, thus demonstrating that Leonardite degradation ability has a limited distribution in bacteria. Hormone-like bioactivities of bHA were also detected. In this study, a bacterial community capable of Leonardite degradation was identified and the products characterized. These data implicate the use of such bacteria for the exploitation of Leonardite as a biofertilizer.     

Isolation and characterization of two forms of glutamine synthetsae from soybean hypocotyl.

Rat skin contains αA and αB collagen the proportion of which changes independently with age. The proportion of αA chains alters more rapidly when compared to αB. It has been also shown that both these collagen categories are closely associated with tissue vasculature. It is suggested that αA and αB constitute two different collagen molecules of the composition (αA)₃ and (αB)₃ respectively.     

Isolation and characterization of the dut gene of Escherichia coli. II. Restriction enzyme mapping and analysis of polypeptide products

Restriction endonuclease mapping of previously constructed dut plasmids has been carried out using the enzymes PvuI, PvuII and SacI. Various dut plasmids were also tested in the "maxicell" protein-synthesizing system. They all show two protein bands in common, one of Mr 16000 in agreement with the size previously reported for the purified dUTPase subunit (Shlomai and Kornberg, 1978). With the information obtained the structural gene for dUTPase can be assigned to a 950-bp SacI-PvuII fragment of the E. coli genome. Studies, described in the preceding paper, on the overproduction of dUTPase by bacterial strains carrying different dut plasmids strongly suggest that the dut gene is transcribed in the direction from the SacI site towards the PvuII site and that the SacI site is located within the dut control region. The second protein band observed in the "maxicell" experiments has an Mr of 23500. Its identity is unknown but it may represent a precursor of dUTPase or the product of a separate gene located between dut and pyrE.     

Isolation and characterization of selenite- and selenate-tolerant microorganisms from selenium-contaminated sites

Eight bacterial strains designated ARI 1-8 were isolated from soil and water samples collected from selenium-contaminated sites in India using the enrichment culture technique. They exhibited very high MIC values ranging from 300 to 750 mM for different forms of selenium (selenite and selenate). On the basis of various biochemical tests, fatty acid methyl ester profile and 16S rRNA gene sequencing, these isolates were identified belonging to the classes β-Proteobacteria and Bacilli. These microorganisms could be further used for bioremediation of contaminated sites.     

Isolation and characterization of novel atrazine-degrading microorganisms from an agricultural soil

Six previously undescribed microorganisms capable of atrazine degradation were isolated from an agricultural soil that received repeated exposures of the commonly used herbicides atrazine and acetochlor. These isolates are all Gram-positive and group with microorganisms in the genera Nocardioides and Arthrobacter, both of which contain previously described atrazine degraders. All six isolates were capable of utilizing atrazine as a sole nitrogen source when provided with glucose as a separate carbon source. Under the culture conditions used, none of the isolates could utilize atrazine as the sole carbon and nitrogen source. We used several polymerase-chain-reaction-based assays to screen for the presence of a number of atrazine-degrading genes and verified their identity through sequencing. All six isolates contain trzN and atzC, two well-characterized genes involved in the conversion of atrazine to cyanuric acid. An additional atrazine-degrading gene, atzB, was detected in one of the isolates as well, yet none appeared to contain atzA, a commonly encountered gene in atrazine impacted soils and atrazine-degrading isolates. Interestingly, the deoxyribonucleic acid sequences of trzN and atzC were all identical, implying that their presence may be the result of horizontal gene transfer among these isolates.     

The fragmentation of actin by thrombin. Isolation and characterization of the split products

Thrombin, a limited protease, hydrolyzes three bonds in actin at Arg-28, Arg-39, and Lys-113, thereby producing two smaller peptides and two larger fragments. The location of the bonds split was identified in the amino acid sequence of actin by isolating the split products and carrying out amino acid analysis, and N- and C-terminal determinations.     

Isolation and characterization of soybean Bowman-Birk inhibitor from different sources

A chromatographic procedure for isolation of different isoforms of Bowman--Birk soybean trypsin inhibitors was developed. The number of isoforms was shown to depend on soybean cultivar. The amount of the classical Bowman--Birk inhibitor (BBI) in different soybean cultivars, commercial flour, and processing products was analyzed. BBI reaches its highest concentration in freshly milled seeds. Storage conditions optimum for preservation of maximum inhibitory activity in soybean raw material were developed. The use of indirect enzyme immunoassay for BBI detection during its isolation from different sources was demonstrated.