3-Methylindole production is regulated in Clostridium scatologenes ATCC 25775.

AIMS: 3-Methylindole (3-MI) is a degradation product of L-tryptophan and is both an animal waste malodorant and threat to ruminant health. Culture conditions influencing 3-MI production in Clostridium scatologenes ATCC 25775 were investigated. METHODS AND RESULTS: Extracellular 3-MI levels in cells cultured in brain heart infusion (BHI) medium (pH 7.0) at 33 degrees C and 37 degrees C for 72 h were 907 +/- 38 and 834 +/- 121 micromol l(-1), respectively. Cells cultured in tryptone-yeast (TY) extract medium at 37 degrees C for 48 h produced 104 +/- 86 micromol l(-1) 3-MI; however, addition of 1 mmol l(-1) L-tryptophan failed to increase extracellular levels (113 +/- 50 micromol l(-1) 3-MI). Specific activity of indole acetic acid decarboxylase measured in BHI, TY and TY plus 1 mmol l(-1) tryptophan-grown cells displayed 35-, 33- and 76-fold higher levels than in semi-defined medium-grown cells. CONCLUSIONS: When cultured in rich medium, at 33 degrees C or 37 degrees C and pH 7.0, Cl. scatologenes ATCC 25775 optimally produced 3-MI. Addition of L-tryptophan to medium did not lead to significant increases in extracellular 3-MI levels. Whole cell assays indicate growth in rich medium significantly up-regulated 3-MI production. SIGNIFICANCE AND IMPACT OF THE STUDY: Information presented here may prove useful in understanding what factors influence 3-MI production in malodorous animal wastes.

Fe(III) stimulates 3-methylindole and 4-methylphenol production in swine lagoon enrichments and Clostridium scatologenes ATCC 25775.

AIMS: To determine the effects of anaerobic electron acceptors on 3-methylindole (3-MI) and 4-methylphenol (4-MP) production in swine lagoon enrichments and Clostridium scatologenes ATCC 25775. METHODS AND RESULTS: Swine lagoon sediment was incubated anaerobically in tryptone-yeast extract medium with (10 mmol l(-1)) Na(2)SO(4), KNO(3), dimethyl sulfoxide or Fe(III). With Fe(III), 3-MI and 4-MP levels increased significantly to 138 +/- 15.8 and 187 +/- 14.0 micromol l(-1), respectively. Clostridium scatologenes cultured in brain-heart infusion medium amended with (10 mmol l(-1)) Na(2)SO(4), KNO(3), MnO(2) or Fe(III), resulted in only Fe(III) significantly increasing 3-MI (1308 micromol l(-1)) and 4-MP (367 micromol l(-1)) levels. In semi-defined medium, Fe(III) alone and Fe(III) + L-tryptophan (1 mmol l(-1)) resulted in a 1.85-fold and 15.6-fold increase in 3-MI levels over L-tryptophan alone, respectively. Fe(III) alone and Fe(III) + L-tyrosine (1 mmol l(-1)) caused a 4.4-fold and 22.9-fold increase in 4-MP levels over tyrosine alone, respectively. Fe(III) did not increase growth of Cl. scatologenes. CONCLUSIONS: Fe(III) increases 3-MI and 4-MP in swine lagoon enrichments and Cl. scatologenes broth cultures. SIGNIFICANCE AND IMPACT OF THE STUDY: Previous studies suggest Fe(III) addition to swine lagoons could remediate malodorous volatile fatty acids; however, here data suggest Fe(III) could increase malodorous indolic and phenolic levels.

Isolation from poultry litter and characterization [corrected] of Staphylococcus spp. capable of growth in high phosphate conditions [corrected].

AIMS: To isolate and characterize micro-organisms from poultry litter capable of growing under phosphate concentrations typical of poultry litter. METHODS AND RESULTS: Poultry litter extracts were plated onto brain-heart infusion medium (BHI) containing an additional 0.75 mol l(-1) phosphate (BHI-P). Colonies were screened for the presence of inclusion granules with five being selected for further study. All strains displayed identical biochemical characteristics consistent with Staphylococcus spp. and grouped with Staphylococcus spp. by comparative 16S rDNA analysis. Thus all five strains were identified as such. All strains displayed elevated intracellular phosphate levels when cultured in BHI-P broth (0.417-0.600 microg phosphate mg(-1) protein) vs BHI broth (0.075-0.093 microg phosphate mg(-1) protein). When grown using an austere semi-defined medium or BHI-P, Staph. sp. #7 displayed similar elevated intracellular phosphate levels compared with growth in BHI. CONCLUSIONS: Poultry litter contains novel Staphylococcus spp. capable of robust growth when exposed to phosphate levels comparable with that typically found in poultry litter. Data suggest intracellular phosphate levels in these strains increase in response to increasing phosphate in the medium or austere medium conditions. Intracellular phosphate did not reach levels comparable with known hyper-accumulating micro-organisms. SIGNIFICANCE AND IMPACT OF THE STUDY: These data suggest poultry litter possesses a resident microflora that thrives and accumulates intracellular phosphate in response to high phosphate conditions.

Nutritional deprivation increases intracellular phosphate and polyphosphate in poultry litter microflora.

AIMS: To determine if mixed microflora from poultry litter accumulates phosphate when deprived of carbon and energy or nitrogen sources. METHODS AND RESULTS: Microbial enrichments from poultry litter capable of metabolizing ammonia, amino acids, and glucose were subjected to nutritional deprivation and the effects on intracellular phosphate levels were determined. Results indicate deprivation of glucose yields a 38 and 50% increase in intracellular phosphate and polyphosphate levels, respectively. Deprivation of nitrogen sources did not result in significant intracellular phosphate accumulation. CONCLUSIONS: Micro-organisms normally present in poultry litter respond to carbohydrate deprivation by accumulating intracellular phosphate. SIGNIFICANCE AND IMPACT OF THE STUDY: Poultry litter typically contains significant levels of phosphate which contribute to environmental pollution when applied to land. Phosphate is highly mobile in soils and often drains into local watersheds following rain events. This study raises the possibility that poultry litter micro-organisms may have the capacity to sequester phosphate, which could delay or diminish phosphate run-off.

Epitope fine specificity of human anti-HLA-A2 antibodies. Identification of four epitopes including a haptenlike epitope on HLA-A2 at lysine 127.

Anti-HLA-A2 CREG antibodies were purified from seven individuals by affinity chromatography. The binding of the purified antibodies to single or multiple amino acid variants of HLA-A2.1 was measured with an inhibition RIA. Substitutions at 10 amino acid residues in the polymorphic alpha 1 and alpha 2 domains were important for human antibody binding; eight of these have previously been shown to be important in the binding of murine anti-HLA-A2 CREG antibodies. Unlike any previously reported murine mAbs, the binding of antibodies from two individuals was eliminated by a substitution at the HLA-A2, -24, -28 shared loop amino acid residue lysine 127. Conversely, when the asparagine at residue 127 on the non-cross-reactive HLA-A3 was replaced with lysine, antibody binding was completely restored. The results further suggest that both lambda- and kappa-containing human antibodies that bind to this region may recognize lysine 127 as a haptenlike epitope. Anti-HLA-A2 antibodies that recognized a conformational epitope defined by changes at glycine 62 in the alpha 1 domain were predominated by lambda light chains whereas those that recognize an epitope defined by a loop residue at tryptophan 107 in the alpha 2 domain were predominated by kappa light chains. The data are consistent with a model of restricted epitope recognition of HLA-A2 by human B cells that is similar to, but distinct from, epitope recognition by mouse B-cell hybridomas, and may help to explain the phenomenon of public or cross-reactive idiotypes in the HLA system.

A strategy to identify the learning needs of staff nurses.

Rapidly changing technology and the trend toward specialization make continuing education (CE) vital for today's nurses. Various methods to assess CE needs of nurses are described in the literature. This article outlines an assessment strategy implemented to determine staff nurses' perceptions of their learning needs. In addition, head nurses and clinical directors were surveyed regarding their perceptions of the staff nurses' learning needs. The chosen strategy used limited resources to contact a large number of nurses within a short time frame. Results indicated that the three groups surveyed perceived similar learning needs for staff nurses.