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161.
Aims: To isolate, characterize and identify lactic acid bacteria (LAB) in the vineyards where koshu grapes, a primary wine grape cultivar in Japan, are grown.
Methods and Results: Sixty samples, including leaves, undamaged grape berries and soil under damaged berries, were collected at four koshu vineyards in Yamanashi Prefecture, Japan. One hundred and 15 acid-producing cultures were isolated from these samples, and the isolates were divided into classes by phenotype and then into groups by restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA (rDNA). Phenotypic and biochemical characteristics identified seven different bacterial groups (A to G). Lactococcus lactis ssp. lactis was the most abundant type of LAB distributed in three koshu vineyards, and Leuconostoc pseudomesenteroides was the most abundant LAB found in the remaining vineyard. Forty-six isolates produced bacteriocin-like inhibitory substances (BLIS) against the indicator strain Lactobacillus sakei JCM 1157T .
Conclusions: These results suggest that various LAB are distributed in koshu vineyards, of which a large number produce BLIS.
Significance and Impact of the Study: This is the first report describing the distribution and varieties of LAB that exist in koshu vineyards. 相似文献
Methods and Results: Sixty samples, including leaves, undamaged grape berries and soil under damaged berries, were collected at four koshu vineyards in Yamanashi Prefecture, Japan. One hundred and 15 acid-producing cultures were isolated from these samples, and the isolates were divided into classes by phenotype and then into groups by restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA (rDNA). Phenotypic and biochemical characteristics identified seven different bacterial groups (A to G). Lactococcus lactis ssp. lactis was the most abundant type of LAB distributed in three koshu vineyards, and Leuconostoc pseudomesenteroides was the most abundant LAB found in the remaining vineyard. Forty-six isolates produced bacteriocin-like inhibitory substances (BLIS) against the indicator strain Lactobacillus sakei JCM 1157
Conclusions: These results suggest that various LAB are distributed in koshu vineyards, of which a large number produce BLIS.
Significance and Impact of the Study: This is the first report describing the distribution and varieties of LAB that exist in koshu vineyards. 相似文献
162.
Cross-linking of ZP2 and ZP3 by transglutaminase is required for the formation of the outer layer of fertilization envelope of carp egg 总被引:3,自引:0,他引:3
A transglutaminase (TGase) cDNA was cloned from carp ovary. It was highly homologous to zebrafish TGase. Immunoblot and enzymatical assay showed that TGase was present on the chorion and in the cytoplasm of carp eggs. Addition of TGase inhibitor, cadaverine or ethylene diaminetetracetic acid (EDTA) to the cortical reaction medium impaired the formation of the outer layer of fertilization envelope (FE(o)), the adhesive structure of carp egg. Fibroin-like substance (FLS), cystatin, cathepsin-like substance (CLS), and FEO-1 were the components of FE(o), wherein the majority of the former three were conjugated to form macromolecules of 90-205 kDa while the latter one was present in monomer of 22 kDa. Cadaverine interfered slightly the discharge of FLS conjugates out of the perivitelline space (PVS) but affected profoundly the recruitment of FLS conjugates to FE, whereas EDTA completely inhibited both the release and the recruitment of FLS conjugates to FE. Both EDTA and cadaverine did not inhibit the discharge of FEO-1 out of PVS but could inhibit the recruitment of FEO-1 to FE. The mechanism was studied. ZP2 and ZP3, the major constituents of inner layer of FE, were cross-linked during cortical reaction, which rendered FE hardened. In the presence of EDTA, the cross-linking of ZP2 and ZP3 were inhibited, thus FE remained soft. The PVS of an egg with a hardened FE was less expanded than an egg with a soft FE. It was assumed that a less expanded PVS would generate a higher fluid pressure than a more expanded PVS did. Therefore, the transportation of the macromolecules such as the FLS-cystatin-CLS conjugates out of PVS was facilitated in control and cadaverine-treated eggs whose FE were hardened but was blocked in EDTA-treated eggs whose FE were unhardened. On the other hand, the transportation of small molecules such as FEO-1 out of FE was not restrained, so they were discharged out of the PVS of the control and TGase inhibitor-treated eggs. In addition, TGase activity was also required for the recruitment of FLS conjugates to FE. 相似文献
163.
Dündaröz MR Türkbay T Sarici SU Akay C Sayal A Denli M 《Biological trace element research》2002,88(2):119-123
Plasma and erythrocyte levels of selenium (Se) and zinc (Zn) have not been investigated in volatile (inhalant) substance abusers
previously, although changes in the activities of antioxidant enzymes resulting from oxidative damage caused by various constituents
of volatile substances have been shown in a few animal and human studies. Concentrations of these two elements in erythrocytes
and plasma of 37 adolescents with inhalant abuse were measured by atomic absorption spectrophotometry and compared with those
of 37 age-matched healthy controls. Erythrocyte and plasma levels of Se and plasma level of Zn were significantly lower in
the study group when compared to the control group. Chronic inhalation of volatile substances can decrease the plasma levels
of Se and Zn and, thus, may lead to a decrease in the activity of antioxidant enzyme systems in adolescent abusers. The role
of Se and Zn supplementation in children with inhalant abuse remains to be determined considering the reduced antioxidant
activity resulting from deficiency of these trace elements. 相似文献
164.
Marilynn E. Etzler Carl Borrebaeck 《Biochemical and biophysical research communications》1980,96(1):92-97
A glycoprotein from the stems and leaves of the plant that cross reacts with antibodies to the seed lectin has been found to bind to affinity columns of blood group A + H substance covalently linked to Sepharose. This binding of the cross reactive material to the affinity resin differs from that of the seed lectin in that it is easily dissociated with 0.15 M NaCl. Affinity electrophoresis using entrapped blood group A + H substance shows that the carbohydrate binding activity of the cross reactive material is weakly inhibited with N-acetyl-D-galactosamine and N-acetyl-D-glucosamine. Glucose, mannose and galactose gave no inhibition when tested at concentrations of 50 mM. These data indicate that the specificity of the cross reactive material is somewhat different from the N-acetyl-D-galactosamine specificity of the seed lectin. The significance of these findings is discussed in relation to the structural similarities of the cross reactive material and the seed lectin. 相似文献
165.
Individuals from a natural population of approximately 20 000 fathead minnows from a pike–free pond did not respond with appropriate anti–predator behaviour upon encountering pike odour in laboratory tests. However, 14 days after 10 pike were stocked into the pond, minnows had acquired recognition of pike odour. Laboratory studies have indicated several possible mechanisms for acquiring predator recognition in fathead minnows. This study indicates that these, or similar processes, can produce major changes in predator recognition in the wild. 相似文献
166.
PHILIP S WANG MATTHIAS ANGERMEYER GUILHERME BORGES RONNY BRUFFAERTS WAI TAT CHIU GIOVANNI DE GIROLAMO JOHN FAYYAD OYE GUREJE JOSEP MARIA HARO YUEQIN HUANG RONALD C KESSLER VIVIANE KOVESS DAPHNA LEVINSON YOSHIBUMI NAKANE MARK A OAKLEY BROWN JOHAN H ORMEL JOSé POSADA-VILLA SERGIO AGUILAR-GAXIOLA JORDI ALONSO SING LEE STEVEN HEERINGA BETH-ELLEN PENNELL SOMNATH CHATTERJI T. BEDIRHAN üSTüN 《World psychiatry》2007,6(3):177-185
Data are presented on patterns of failure and delay in making initial treatment
contact after first onset of a mental disorder in 15 countries in the World
Health Organization (WHO)''s World Mental Health (WMH) Surveys. Representative
face-to-face household surveys were conducted among 76,012 respondents aged
18 and older in Belgium, Colombia, France, Germany, Israel, Italy, Japan,
Lebanon, Mexico, the Netherlands, New Zealand, Nigeria, People''s Republic
of China (Beijing and Shanghai), Spain, and the United States. The WHO Composite
International Diagnostic Interview (CIDI) was used to assess lifetime DSM-IV
anxiety, mood, and substance use disorders. Ages of onset for individual disorders
and ages of first treatment contact for each disorder were used to calculate
the extent of failure and delay in initial help seeking. The proportion of
lifetime cases making treatment contact in the year of disorder onset ranged
from 0.8 to 36.4% for anxiety disorders, from 6.0 to 52.1% for mood disorders,
and from 0.9 to 18.6% for substance use disorders. By 50 years, the proportion
of lifetime cases making treatment contact ranged from 15.2 to 95.0% for anxiety
disorders, from 7.9 to 98.6% for mood disorders, and from 19.8 to 86.1% for
substance use disorders. Median delays among cases eventually making contact
ranged from 3.0 to 30.0 years for anxiety disorders, from 1.0 to 14.0 years
for mood disorders, and from 6.0 to 18.0 years for substance use disorders.
Failure and delays in treatment seeking were generally greater in developing
countries, older cohorts, men, and cases with earlier ages of onset. These
results show that failure and delays in initial help seeking are pervasive
problems worldwide. Interventions to ensure prompt initial treatment contacts
are needed to reduce the global burdens and hazards of untreated mental disorders. 相似文献
167.
In producing power, humans move the nutrients nitrogen (N) and phosphorus (P) from their long‐term geological and biological stocks and release or emit them in soil, water, and the atmosphere. In Finland, peat combustion is an important driver of N and P fluxes from the environment to human economy. The flows of N and P in the Finnish energy system were quantified with partial substance flow analysis, and the driving forces of emissions of nitrogen oxides (NOx) were analyzed using the ImPACT model. In the year 2000 in Finland, 140,000 tonnes of nitrogen entered the energy system, mainly in peat and hard coal. Combustion released an estimated 66,000 tonnes of N as nitrogen oxides (NOx) and nitrous oxides (N2O) and another 74,000 tonnes as elemental N2. Most of the emissions were borne in traffic. At the same time, 6,000 tonnes of P was estimated to enter the Finnish energy system, mostly in peat and wood. Ash was mainly used in earth construction and disposed in landfills; thus negligible levels of P were recycled back to nature. During the twentieth century, fuel‐borne input of N increased 20‐fold, and of P 8‐fold. In 1900–1950, the increasing use of hard coal slowly boosted N input, whereas wood fuels were the main carrier of P. Since 1970, the fluxes have been on the rise. NOx emissions leveled off in the 1980s, though, and then declined in conjunction with improvements in combustion technologies such as NOx removal (de‐NOx) technologies in energy production and catalytic converters in cars. 相似文献
168.
目的获取高产抑制鸡白痢沙门菌生长的类细菌素乳酸乳球菌的突变菌株。方法在紫外线照射致死率为82.7%的剂量下,对处于对数生长后期的乳酸乳球菌V528进行紫外线二次复合诱变处理。分别随机对第一次和第二次复合处理后生长的117株和310株菌进行效价测定分析。结果在实验所用的照射剂量下,抑菌效价提高的正突变菌株占有一定优势,负突变菌株较少,其中突变菌株Lact.174的抑菌效价较V528的效价提高了8.48倍,并具有一定的遗传稳定性。结论运用紫外诱变育种技术可有效地获得高产类细菌素的突变菌株。 相似文献
169.
170.
CLAYTON T. JAMES BRIAN D. WISENDEN CAMERON P. GOATER 《Biological journal of the Linnean Society. Linnean Society of London》2009,98(4):884-890
Epidermal club cells of fishes in the superorder ostariophysi have puzzled evolutionary biologists because they were historically linked to chemical alarm signalling and relied on group selectionist explanations. Alternative hypotheses to explain the existence of these cells include the possibility of an anti‐pathogenic or anti‐parasitic function. If this is so, individual fish should invest in increased numbers of club cells after exposure to parasites, and club cells should contain components that reduce the infectivity of skin‐penetrating larvae. Infectivity of cercariae of the trematode Ornithodiplostomum sp. was significantly reduced when exposed to the skin extract of fathead minnows (an ostariophysan), but also to skin extract of mollies (a non‐ostariophysan that lacks club cells), respectively, compared to controls. Moreover, club cell density was not affected by exposure to cercariae. Taken together, these results are inconsistent with an anti‐parasite function for these cells and instead suggest a generic role in response to injury. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98 , 884–890. 相似文献