Abstract:
:The routine production and storage of frozen doughs are still problematic. Although commercial baker's yeast is highly resistant to environmental stress conditions, it rapidly loses stress resistance during dough preparation due to the initiation of fermentation. As a result, the yeast loses gassing power significantly during storage of frozen doughs. We obtained freeze-tolerant mutants of polyploid industrial strains following screening for survival in doughs prepared with UV-mutagenized yeast and subjected to 200 freeze-thaw cycles. Two strains in the S47 background with a normal growth rate and the best freeze tolerance under laboratory conditions were selected for production in a 20-liter pilot fermentor. Before frozen storage, the AT25 mutant produced on the 20-liter pilot scale had a 10% higher gassing power capacity than the S47 strain, while the opposite was observed for cells produced under laboratory conditions. AT25 also retained more freeze tolerance during the initiation of fermentation in liquid cultures and more gassing power during storage of frozen doughs. Other industrially important properties (yield, growth rate, nitrogen assimilation, and phosphorus content) were very similar. AT25 had only half of the DNA content of S47, and its cell size was much smaller. Several diploid segregants of S47 had freeze tolerances similar to that of AT25 but inferior performance for other properties, while an AT25-derived tetraploid, TAT25, showed only slightly improved freeze tolerance compared to S47. When AT25 was cultured in a 20,000-liter fermentor under industrial conditions, it retained its superior performance and thus appears to be promising for use in frozen dough production. Our results also show that a diploid strain can perform at least as well as a tetraploid strain for commercial baker's yeast production and usage.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Teunissen A,Dumortier F,Gorwa MF,Bauer J,Tanghe A,Loïez A,Smet P,Van Dijck P,Thevelein JMdoi
10.1128/aem.68.10.4780-4787.2002keywords:
subject
Has Abstractpub_date
2002-10-01 00:00:00pages
4780-7issue
10eissn
0099-2240issn
1098-5336journal_volume
68pub_type
杂志文章abstract::By using thin-layer chromatography and infrared spectroscopy, xanthomegnin and viomellein have been isolated and identified from species of the Aspergillus ochraceus group. A correlation was established between the occurrence of these fungal quinones in the fungal cultural products and the ability of these products to...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.36.6.819-823.1978
更新日期:1978-12-01 00:00:00
abstract::The role of the storage lipid poly-beta-hydroxybutyrate (PHB) in trichloroethylene transformation by methanotrophic mixed cultures was investigated. Naphthalene oxidation rates were used to assay for soluble methane monooxygenase activity. The PHB content of methanotrophic cells grown in reactors varied diurnally as w...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.59.5.1602-1606.1993
更新日期:1993-05-01 00:00:00
abstract::Heavy metal resistance by bacteria is a topic of much importance to the bioremediation of contaminated soils and sediments. We report here the isolation of a highly cadmium-resistant Klebsiella planticola strain, Cd-1, from reducing salt marsh sediments. The strain grows in up to 15 mM CdCl(2) under a wide range of Na...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.7.3083-3087.2000
更新日期:2000-07-01 00:00:00
abstract::A multilocus enzyme electrophoresis analysis of 96 strains of the salmonellae distinguished 80 electrophoretic types (ETs) and placed them in eight groups, seven of which correspond precisely to the seven taxonomic groups (I, II, IIIa, IIIb, IV, V, and VI) previously defined on the basis of biotype and genomic DNA hyb...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.3.804-808.1996
更新日期:1996-03-01 00:00:00
abstract::Three Methocel methylcellulose ethers of 1.9 degree of substitution with [14C]methyl labels were shown to be biodegradable using batch-type activated sludge tests. The maximum rate for conversion to 14CO2, attained after 1 week, was only 0.62 mg of methylcellulose/g of mixed liquor volatile solids per day. In 20 days,...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.32.4.557-560.1976
更新日期:1976-10-01 00:00:00
abstract::Escherichia coli, a commensal bacterium from the intestinal tracts of humans and vertebrate animals, has been used as one of two bacterial indicators of fecal contamination, along with intestinal enterococci, to monitor the microbiological quality of water. However, water environments are now recognized as a secondary...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.00698-13
更新日期:2013-08-01 00:00:00
abstract::Biodesulfurization was monitored in a recombinant Pseudomonas putida CECT5279 strain. DszB desulfinase activity reached a sharp maximum at the early exponential phase, but it rapidly decreased at later growth phases. A model two-step resting-cell process combining sequentially P. putida cells from the late and early e...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01682-08
更新日期:2009-02-01 00:00:00
abstract::Dairy propionic acid bacteria, particularly the species Propionibacterium freudenreichii, play a major role in the ripening of Swiss type cheese. Isometric and filamentous bacteriophages infecting P. freudenreichii have previously been isolated from cheese. In order to determine the origin of these bacteriophages, lys...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.67.1.231-238.2001
更新日期:2001-01-01 00:00:00
abstract::A device for sampling at depths of up to 6,000 m is described in which 3 liters of seawater is concentrated over a Nucleopore filter to about 13 ml and retrieved under in situ pressure and temperature. Subsamples can be withdrawn into transfer units that are equipped with individual gas accumulators for preventing los...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.33.3.642-646.1977
更新日期:1977-03-01 00:00:00
abstract::Water resources contaminated with wastewater are an important source for the dissemination of enteric viruses with an impact on the health of the population. The aim of the study was to assess the viral contamination of freshwater from a dam in Argentina by using infectious enterovirus detection, viral RNA amplificati...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02327-17
更新日期:2018-02-14 00:00:00
abstract::A stable shuttle vector which replicates in Escherichia coli and Clostridium perfringens was constructed by ligating a 3.6-kilobase (kb) fragment of plasmid pBR322 with C. perfringens plasmid pHB101 (3.1 kb). The marker for this shuttle plasmid originated from the 1.3-kb chloramphenicol resistance gene of plasmid pHR1...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.55.2.360-365.1989
更新日期:1989-02-01 00:00:00
abstract::Indoxyl-beta-D-glucuronide (indoxyl) was evaluated as a specific chromogen for detection of Escherichia coli by the membrane filter method. In all, 413 colonies were tested from the indoxyl-supplemented media, yielding 93.3% confirmation, as E. coli. Compared with the indoxyl medium, other media gave either much lower...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.59.8.2758-2759.1993
更新日期:1993-08-01 00:00:00
abstract::The internal transcribed spacer (ITS) of the gene coding for rRNA was sequenced in both directions with the gene walking technique in a black morel (Morchella conica) and a yellow morel (M. esculenta) to elucidate the ITS length discrepancy between the two species groups (750-bp ITS in black morels and 1,150-bp ITS in...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.9.3541-3543.1996
更新日期:1996-09-01 00:00:00
abstract::Growth of the ruminal bacteria Fibrobacter succinogenes S85, Ruminococcus flavefaciens FD-1, and R. albus 7 followed Monod kinetics with respect to concentrations of individual pure cellodextrins (cellobiose, cellotriose, cellotetraose, cellopentaose, and cellohexaose). Under the conditions tested, R. flavefaciens FD-...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.3.1084-1088.1996
更新日期:1996-03-01 00:00:00
abstract::Although it is widely believed that horizontal patchiness exists in microbial sediment communities, determining the extent of variability or the particular members of the bacterial community which account for the observed differences among sites at various scales has not been routinely demonstrated. In this study, hor...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.5.1980-1986.2000
更新日期:2000-05-01 00:00:00
abstract::Root-colonizing, saprophytic fluorescent pseudomonads of the Pseudomonas putida-P. fluorescens group express similar levels of catalase and superoxide dismutase activities during growth on a sucrose- and amino acid-rich medium. Increased specific activities of catalase but not superoxide dismutase were observed during...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.56.11.3576-3582.1990
更新日期:1990-11-01 00:00:00
abstract::Cold shock at 0 to 15 degrees C for 1 to 3 h increased the thermal sensitivity of Listeria monocytogenes. In a model broth system, thermal death time at 60 degrees C was reduced by up to 45% after L. monocytogenes Scott A was cold shocked for 3 h. The duration of the cold shock affected thermal tolerance more than did...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.10.4345-4350.2000
更新日期:2000-10-01 00:00:00
abstract::Enzymatic activities that could be involved in methanethiol generation in five cheese-ripening bacteria were assayed, and the major sulfur compounds produced were identified. L-Methionine and alpha-keto-gamma-methyl-thio-butyric acid demethiolating activities were detected in whole cells and cell extracts (CFEs) of al...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.66.12.5514-5517.2000
更新日期:2000-12-01 00:00:00
abstract::Leghorn hens over 50 weeks of age were assigned to two treatment groups designated as either unmolted controls or molted. A forced molt was induced by a 9-day feed withdrawal, and each hen was challenged orally with 10(5) Salmonella enteritidis organisms on day 4 of feed withdrawal. On days 4 and 9 of molt, the number...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.65.5.1919-1923.1999
更新日期:1999-05-01 00:00:00
abstract::The occurrence, structure, and mobility of Tn1546-like elements were studied in environmental vancomycin-resistant enterococci (VRE) isolated from municipal sewage, activated sludge, pharmaceutical waste derived from antibiotic production, seawater, blue mussels, and soil. Of 200 presumptive VRE isolates tested, 71 (3...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.70.2.984-990.2004
更新日期:2004-02-01 00:00:00
abstract::The bifidobacterial and lactobacillus populations of fecal samples collected from two human subjects during a 12-month period were studied. The total numbers of bifidobacteria were stable throughout the study period in both subjects, but lactobacillus numbers were less constant. Analysis of the composition of the bifi...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.12.4608-4613.1996
更新日期:1996-12-01 00:00:00
abstract::The world's largest outbreak of waterborne toxoplasmosis occurred in a municipality in the western Canadian province of British Columbia. When drinking water emerged as a possible source of infection during the outbreak investigation, a laboratory method was needed to attempt detection of the parasite, Toxoplasma gond...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.64.6.2278-2280.1998
更新日期:1998-06-01 00:00:00
abstract::A genomic clone bank of Acetobacter polyoxogenes NBI1028 constructed in Escherichia coli by use of the expression vector pUC18 was screened with antibody raised against membrane-bound aldehyde dehydrogenase (ALDH; 75 kilodaltons [kDa]) from A. polyoxogenes NBI1028. A clone that synthesized a 41-kDa protein cross-react...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.55.1.171-176.1989
更新日期:1989-01-01 00:00:00
abstract::rRNA internal transcribed spacer phylogeny showed that Chesapeake Bay is populated with diverse Synechococcus strains, including members of the poorly studied marine cluster B. Marine cluster B prevailed in the upper bay, while marine cluster A was common in the lower bay. Interestingly, marine cluster B Synechococcus...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.72.3.2239-2243.2006
更新日期:2006-03-01 00:00:00
abstract::Dehalobacter and "Dehalococcoides" spp. were previously shown to be involved in the biotransformation of 1,1,2-trichloroethane (1,1,2-TCA) and 1,2-dichloroethane (1,2-DCA) to ethene in a mixed anaerobic enrichment culture. Here we report the further enrichment and characterization of a Dehalobacter sp. from this mixed...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02037-08
更新日期:2009-05-01 00:00:00
abstract::The role of protease produced by a heterotrophic bacterium during growth was investigated with Aeromonas salmonicida, the pathogen of fish furunculosis, strain A-7301 and its protease-deficient mutant NTG-1 induced by mutagenesis. Strain A-7301 produced extracellular protease in a mixed amino acid medium (composed of ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.50.4.1031-1037.1985
更新日期:1985-10-01 00:00:00
abstract::Pyrobaculum islandicum uses iron, thiosulfate, and elemental sulfur for anaerobic respiration, while Pyrobaculum aerophilum uses iron and nitrate; however, the constraints on these processes and their physiological mechanisms for iron and sulfur reduction are not well understood. Growth rates on sulfur compounds are h...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02033-07
更新日期:2008-01-01 00:00:00
abstract::The cholera toxin genes of Vibrio cholerae are encoded by CTXΦ, a lysogenic bacteriophage. Infection with this phage plays a determinant role in toxigenicity conversion and the emergence of new clones of pathogenic V. cholerae. Multiple phage alleles, defined by sequence types of the repressor gene rstR, have been fou...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01742-15
更新日期:2015-10-01 00:00:00
abstract::Xanthobacter flavus 14p1 was isolated from sludge of the river Mulde by selective enrichment with 1,4-dichlorobenzene as the sole source of carbon and energy. The bacterium did not use other aromatic or chloroaromatic compounds as growth substrates. During growth on 1,4-dichlorobenzene, stoichiometric amounts of chlor...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.11.3884-3888.1995
更新日期:1995-11-01 00:00:00
abstract::"Candidatus Methanoperedens nitroreducens" is an archaeon that couples the anaerobic oxidation of methane to nitrate reduction. In natural and man-made ecosystems, this archaeon is often found at oxic-anoxic interfaces where nitrate, the product of aerobic nitrification, cooccurs with methane produced by methanogens. ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01832-18
更新日期:2018-11-30 00:00:00