<Emphasis Type="Italic">Hymeniacidon perleve</Emphasis> associated bioactive bacterium <Emphasis Type="Italic">Pseudomonas</Emphasis> sp. NJ6-3-1

Among marine bacteria isolated from the cytotoxic sponge Hymeniacidon perleve, one strain NJ6-3-1 classified as Pseudomonas sp. showed both cytotoxic and antimicrobial activities. Fatty acid analysis indicated that the bacterial strain consists mainly of C16:1, C16:0, C18:1, C18:0, C15:0, C14:0. One unusual 9,10-cyclopropane-C17:0 fatty acid and C26:0 also constitute major components, as well as the existence of squalene, the precursor of triterpenoids. The major metabolites in the culture broth were identified as alkaloids, including diketopiperazines and indole compounds, namely 3,6-diisopropylpiperazine-2,5-dione, 3-benzyl-3-isopropylpiperazine-2,5-dione, 3,6-bis-(2-methylpropyl)-piperazine-2,5-dione, indole-3-carboxaldehyde, indole-3-carboxylic acid methyl ester, indole-3-ethanol, and quinazoline-2,4-dione.From Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 1, 2005, pp. 35–39.Original English Text Copyright © 2005 by Li Zheng, Xiaojun Yan, Jilin Xu, Haimin Chen, Wei Lin.This article was submitted by the authors in English.     

Effect of Humic Substances on the Growth of Microalgal Cultures

Treatment with humic substances (preparation Biomin) considerably increased viability of algae during long storage (6 months) in collection. The effect was greater with green algae (Scenedesmus and Chlorella) than with blue-green algae (Nostoc and Anabaena). In intensive cultures, lower Biomin concentrations (1–10 mg/l) increased the biomass production, protein, chlorophyll and carotenoid content, as well as -esterase and glutamate dehydrogenase activities, whereas the lipid and carbohydrate content was higher at 100 mg/l Biomin. A high Biomin concentration (1 g/l) exerted an inhibition. Biomin supply to the cultures in outdoor installation of Shetlik type was associated with a moderate stimulation of algal biomass accumulation. It was concluded that Biomin might be helpful in the improvement of algal viability and growth.__________From Fiziologiya Rastenii, Vol. 52, No. 3, 2005, pp. 463–466.Original English Text Copyright © 2005 by Pouneva.This article was submitted by the author in English.     

Cloning and Production of a Novel Bacteriocin, Lactococcin K, from Lactococcus lactis Subsp. lactis MY23

A gene encoding the antimicrobial peptide, lactococcin K, was isolated from Lactococcus lactis subsp. lactis MY23 then cloned and expressed in Escherichia coli. Because the expressed lactococcin K was formed as an inclusion body in recombinant E. coli, a fusion protein containing lactococcin K and maltose-binding protein (MBP) was produced in a soluble form. For high-level production of lactococcin K, we performed a pH-stat fed-batch culture to produce 43,000 AU lactococcin K ml⁻¹ in 12 h. Revisions requested 3 November 2005; Revisions received 7 December 2005     

Cumulative effect of low and high atrazine concentrations on <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis> plants

Atrazine belongs to the widely used herbicides blocking the electron transport chain in chloroplasts, thus resulting in the generation of active oxygen species. In the present work, we demonstrated that, at low concentrations mimicking residual amounts, atrazine enhanced the susceptibility of Arabidopsis plants to further treatments with the same herbicide applied at the recommended field rate. Arabidopsis thaliana plants were treated three times (at five-day intervals) with 1 µM atrazine. Five days after the last treatment, the plants were sprayed with 5 mM atrazine. Atrazine increased the levels of lipid peroxidation products, hydrogen peroxide, and ion leakage, and caused changes in the activities of antioxidant enzymes, such as superoxide dismutase, guaiacol peroxidase, and catalase.From Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 243–249.Original English Text Copyright © 2005 by Ivanov, Alexieva, Karanov.This article was submitted by the authors in English.This revised version was published online in April 2005 with a corrected cover date.     

Molecular Manipulation and Modification of the <Emphasis Type="Italic">Gy2</Emphasis> and <Emphasis Type="Italic">Gy4</Emphasis> Genes Encoding Glycinin Subunits in Soybean Seeds

The Gy2 and Gy4 genes encoding glycinin subunits were molecularly manipulated and modified to test the possibility of increasing the nutritional value of soybean seed proteins. With the respective recombinant DNAs (pSP65/G2HG4, pSP65/G4HG2, pSP65/248Metl, pSP65/248Met2,3, and pSP65/248Metl,2,3), the in vitro translation was used to produce (i) chimeric proteins consisting of reciprocally exchanged acidic and basic domains of the G2 and G4 subunits, and (ii) G4 point mutants with increased number of methionine residues. The ability of the recombinant proteins to assemble into proper quaternary structures was inspected by sucrose gradient fractionation. The produced data could provide valuable clues for the potential improvement of the genetically modified crops.__________From Fiziologiya Rastenii, Vol. 52, No. 3, 2005, pp. 412–420.Original English Text Copyright © 2005 by Sammour.This article was submitted by the author in English.     

The Frequencies of the Serum Amyloid A2 Alleles in Healthy (Turkish,Azerbaijani, and Kazakh) Populations

The Amyloid A1 (AA1) and A2 (AA2) proteins, which result from proteolytic cleavage of the Serum Amyloid A1 (SAA1) and A2 (SAA2) proteins, are major protein components of the Amyloid A deposits found in secondary amyloidosis. This study determines frequency of serum amyloid A2 alleles (α, β) in healthy Turkish, Azerbaijani, and Kazakh subjects. Two hundred Turkish, sixty-five Azerbaijani and sixty-five Kazakh healthy individuals were studied by previously described the PCR-RFLP methods. Our data revealed that the frequencies of the α and β alleles at the SAA2 locus in the Turkish healthy population were different when compared to those in Azerbaijani and Kazakh healthy populations (P = 0.014 and 0.02), respectively. In contrast, the difference between α and β alleles at the SAA2 locus was not different in both Kazakh and Azerbaijani healthy populations (P = 0.882).From Genetika, Vol. 41, No. 7, 2005, pp. 986–989.Original English Text Copyright © 2005 by Hakki Tastan, Ozlem Osmanagaoglu, Ayla Tuzun.The text was submitted by the authors in English.     

Purified Recombinant Phage Lysin LySMP: An Extensive Spectrum of Lytic Activity for Swine Streptococci

Bacteriophage lysin has attracted considerable attentions as possible antimicrobial agents for solution of antibiotic resistance. SMP was a Streptococcus suis serotype 2 bacteriophage isolated from nasal swabs of healthy Bama minipigs. The putative SMP bacteriophage lysin, designated LySMP, was recombinantly expressed in Escherichia coli BL21, and chromatographically purified. Treated with 0.8% of β-mercaptoethanol, LySMP exhibited an extensive lysin spectrum than those of whole phage against bacteria investigated. S. suis serotype 2, S. suis serotype 7 and S. suis serotype 9 strains were recovered from diseased pigs between 1998 and 2005 in China. Fifteen of seventeen strains of S. suis serotype 2 could be lysed, as well as S. suis serotype 7 and 9, Streptococcus equi ssp. zooepidemicus and Staphylococcus aureus. But E. coli and Salmonella enterica were not affected. Purified LySMP showed high degrading efficiency against PMSF or lysozyme treated cells comparing to PBS washed cells. Optimum pH and temperature conditions for the lysin were investigated by turbidity reduction assay. The lysin exerted efficient lysis activity at 37°C, pH 5.2. The turbidity of bacterium investigated was observed to decrease by 1.2–68% in 30 min. Result indicated that putative LySMP could be a candidate antimicrobial agent in controlling S. suis infection.     

Sequence of a cDNA Encoding Turtle High Mobility Group 1 Protein

In order to understand sequence information about turtle HMG1 gene, a cDNA encoding HMG1 protein of the Chinese soft-shell turtle (Pelodiscus sinensis) was amplified by RT-PCR from kidney total RNA, and was cloned, sequenced and analyzed. The results revealed that the open reading frame (ORF) of turtle HMG1 cDNA is 606 bp long. The ORF codifies 202 amino acid residues, from which two DNA-binding domains and one polyacidic region are derived. The DNA-binding domains share higher amino acid identity with homologous sequences of chicken (96.5%) and mammals (74%) than homologous sequence of rainbow trout (67%). The polyacidic region shows 84.6% amino acid homology with the equivalent region of chicken HMG1 cDNA. Turtle HMG1 protein contains 3 Cys residues located at completely conserved positions. Conservation in sequence and structure suggests that the functions of turtle HMG1 cDNA may be highly conserved during evolution. To our knowledge, this is the first report of HMG1 cDNA sequence in any reptilian.From Genetika, Vol. 41, No. 7, 2005, pp. 925–930.Original English Text Copyright © 2005 by Jifang Zheng, Bi Hu, Duansheng Wu.The text was submitted by the authors in English.     

Genetic Regulation on the Black Phenotype Mutants of Moth and Pupa of <Emphasis Type="Italic">Helicoverpa armigera</Emphasis> (Lepidoptera: Noctuidae)

Genetic regulation of body color of mutant strain JBM of Helicoverpa armigera with black body color of pupae and adults was investigated. Reciprocal crosses between JBM and JBW (a wild strain with yellow brown body color of pupae and adults) were used to determine the inheritance characteristics of body color. Analysis of the ratio of phenotype segregation from the F₁ generation, F₂ generation, F₃ generation, BC₁ (F₁ × JBM) generation and F₁ generation of BC₁ indicated that the black body color was controlled by one recessive gene.__________From Genetika, Vol. 41, No. 5, 2005, pp. 702–704.Original English Text Copyright © 2005 by Wang Mo, Weihua Ma, Lizhen Chen, Fuxing Zhu, Jianhong Li.This article was submitted by the authors in English.     

Variation in survival of <Emphasis Type="Italic">Iris pumila</Emphasis> L. juvenile plants grown in two nutrient regimes

I analyzed variability of early life survival on 881 Iris pumila juvenile plants in their prereproductive period. Seedlings were produced by applying half-sib mating scheme on clones originating from two Deliblato Sand populations that were accommodated to common garden conditions. Nineteen clones served as pollen donors (sires) and the other 90 clones served as pollen recipients (dames). Seedlings were grown in two nutrient levels (full strength and 1/10 of full-strength Hoagland solution). While I failed to detect significant mean nutrient level effect as well as significant between population differentiation for prereproductive survival, a statistically significant additive genetic variability for this ultimate prereproductive measure of fitness was detected.From Genetika, Vol. 41, No. 2, 2005, pp. 279–282.Original English Text Copyright © 2005 by Tarasjev.This article was submitted by the author in English.     

Antioxidant capacity of <Emphasis Type="Italic">Brassica juncea</Emphasis> plants exposed to elevated levels of copper

Brassica juncea L. eight-day-old seedlings treated with various concentrations (50–200 µM) of copper for 48 h accumulated Cu more in the roots than in leaves. Accumulation of copper resulted in more active lipid peroxidation and depletion of glutathione (GSH) pools in both roots and shoots, which was attributed to copper-induced additional oxidative stress. Activities of ascorbate peroxidase and superoxide dismutase were higher in both roots and shoots while catalase activity increased in leaves but remained unchanged in roots in response to copper accumulation. Changes in lipid peroxidation, GSH content, and antioxidant enzyme activities suggest that oxidative damage may be involved in copper toxicity.From Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 233–237.Original English Text Copyright © 2005 by Devi, Prasad.This article was submitted by the authors in English.This revised version was published online in April 2005 with a corrected cover date.     

Re-occurrence and bioindication status of the netted dog whelk <Emphasis Type="Italic">Nassarius reticulatus</Emphasis> (Linnaeus, 1758) in the Western Baltic Sea (Mecklenburg Bight,Germany)

The netted dog whelk Nassarius reticulatus (Linnaeus, 1758), considered as an extinct benthic species in German Baltic waters, was found again alive in the Mecklenburg Bight during several macrozoobenthic surveys since 1997. All data indicate that the establishment of this marine prosobranch species is connected with the more frequent intrusions of highly saline water from the North Sea into the Baltic that have been observed over the past few years. It is proposed that N. reticulatus is a good bioindicator for the hydrographic status in the western Baltic rather than for other existing potential conditions. Since 1998 a second extinct marine species, the polychaete Scalibregma inflatum Rathke, 1843 was found alive here, too.Original English Text Copyright © 2005 by Biologiya Morya, Nehring.This article was submitted by the author in English.     

Synthesis and Biological Activities of New 1,2,4-Triazol-3-one Derivatives

New 2-phenacyl-1,2,4-triazol-3-ones were obtained by the reaction of 5-alkyl-1,2,4-triazol-3-ones with α-bromoacetophenone in an alkaline medium. Selective reduction of the side chain carbonyl group to hydroxy group was achieved with NaBH₄. The reaction of some compounds containing a phenolic hydroxyl with 4-toluenesulfonyl chloride or benzyl bromide in the presence of NaOH led to tosylated or benzylated derivatives. The tosylation or benzylation at the alcoholic hydroxyl was carried out in the presence of sodium metal. Some of the newly synthesized compounds revealed an antimicrobial activity; 6 of 14 new compounds that were studied by the National Cancer Institute were found to possess antitumor activity.__________Translated from Bioorganicheskaya Khimiya, Vol. 31, No. 4, 2005, pp. 430–440.Original Russian Text Copyright ¢ 2005 by N. Demirbas, A. Demirbas, Karaoglu.The text was submitted by the authors in English.     

Prevalence of verotoxigenic Escherichia coli O157 (VTEC O157) and compliance with microbiological safety standards in bovine carcasses from an industrial beef slaughter plant

The presence of Salmonella spp. and levels of Enterobacteriaceae and aerobic plate count were determined in 300 bovine carcasses randomly collected in an industrial cattle slaughterhouse in Catalonia (Spain) as part of a control programme to validate good slaughter practices according to Commission Regulation No 2073/2005. The verotoxigenic Escherichia coli O157 (VTEC O157), although not currently legislated, was also investigated in the same carcasses due to the importance of bovines as a reservoir for this micro‐organism. Virulence genes (vtx1, vtx2 and eae), the presence of fliC_H7 and antimicrobial susceptibility were studied in E. coli O157 isolates. Levels of Enterobacteriaceae and aerobic colonies and the presence of Salmonella were within the admissible range stipulated by current legislation. However, VTEC O157 was detected in 14·7% of carcasses. Among the VTEC O157 strains tested for antimicrobial susceptibility, 65% were multiresistant. Overall, the results of this study indicate that even with good manufacturing practices, contamination with VTEC O157 can occur and cattle meat can pose a risk to human health. These results confirm the need for a review of the appropriateness of introducing antimicrobial treatments in the processing of cattle carcasses in Europe.

Significance and Impact of the Study

This study describes the prevalence of verotoxigenic and multidrug‐resistant E. coli O157 strains in bovine carcasses. These results suggest that despite the good manufacturing practices used in the slaughterhouse studied (the largest in Catalonia slaughtering over 81 000 cattle per year), the absence of verotoxigenic E. coli O157 in bovine carcasses cannot be guaranteed.     

In vitro assay of the antimicrobial activity of kephir against bacterial and fungal strains

Kephir is a fermented carbonated refreshing milk, with a slightly acidic aromatic taste and creamy foam composition which contains lactobacilli, leuconostocci, acetic acid bacteria, lactostreptococci and yeasts. Recent studies have demonstrated its antibacterial, immunostimulating, antitumoral and cholesterol-lowering activities.

Purpose

The purpose of this study was to investigate the antimicrobial activity of kephir against Bacillus subtilis spp. spizizenii ATCC 6633, Staphylococcus aureus ATCC 6538, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 8739, Salmonella enteritidis ATCC 13076, Pseudomonas aeruginosa ATCC 9027 and Candida albicans ATCC 10231. The kephir fermented for 24 h and 48 h, as well and after 7 days preservation at 4–8 °C was tested by in vitro disk diffusion method. The intensity of the antimicrobial activity was interpreted by comparison with two antibiotics, i.e. ampicillin and neomycin.

Results

The antimicrobial activity of 24 h as well as 48 fermented kephir, fresh or after 7 days preservation at 4–8 °C was similar and observed against B. subtilis, S. aureus, E. coli, E. faecalis and S. enteritidis. For E. coli, E. faecalis and S. enteritidis the antimicrobial activity was superior to both tested antibiotics and for B. subtilis and S. aureus to one antibiotic. The tested products exhibited no activity against P. aeruginosa and C. albicans.

Conclusion

Kephir is exhibiting large spectrum and strong antibacterial activity probably due to the complex viable probiotic strains association producing antimicrobial substances.     

Effects of salinity on the contents of polyamines and some other compounds in sunflower plants differing in salt tolerance

The effects of salt stress (50, 100, and 150 mM NaCl) on the levels of free, bound, and total polyamines were studied in the leaf tissues of salt-tolerant (Coban) and salt-sensitive (Sanbro) cultivars of sunflower (Helianthus annuus L.) plants grown for 15 or 25 days under salinity. The amounts of free, acid-soluble bound, and total spermine increased in leaf tissues of sunflower plants subjected to salt stress while the levels of other polyamines decreased or no significant changes occurred. The increase in some PA titers suggests their potential role in overcoming the adverse effect of salinity stress. The salt sensitivity of the sunflower plants was associated with the excessive accumulation of total polyamines in the leaf tissues of salt-sensitive cultivar (Sanbro) under saline condition. The content of other compounds such as proline, protein, and ions (Na⁺, K⁺, Cl^-, K⁺/Na⁺) in leaf tissue changed depending on salt concentration and the cultivars used.From Fiziologiya Rastenii, Vol. 52, No. 1, 2005, pp. 36–42.Original English Text Copyright © 2005 by Mutlu, Bozcuk.This article was presented by the authors in English.     

Wild black-headed gulls (<Emphasis Type="Italic">Larus ridibundus</Emphasis>) as an environmental reservoir of <Emphasis Type="Italic">Salmonella</Emphasis> strains resistant to antimicrobial drugs

Salmonella were isolated from black-headed gulls (Larus ridibundus) in six locations in the Czech Republic from 1984 to 2005 (Chropyně and Nymburk in 1984–1986; Nové Mlyny, Bartošovice, and Hodonín in 1991–1994; and Nové Mlyny, Bartošovice, and Ostrava in 2005). Antimicrobial susceptibility was determined in 12 antimicrobial drugs using disk diffusion. Although 95% of Salmonella isolates (197 out of 207) were pansusceptible, the prevalences of resistance increased significantly from 1 (2%) out of 59 isolates in 1984–1986 and 3 (3%) out of 100 isolates in 1991–1994 to 6 (13%) out of 48 isolates in 2005. Furthermore, in 2005, two isolates were nalidixic acid-resistant and one isolate was multidrug-resistant Salmonella Typhimurium DT 104. These findings suggest that the occurrence of salmonellae in black-headed gulls depends to a large extent on the contamination where the gulls feed and possibly reflects the dissemination of these strains among farm animals and humans. Black-headed gulls may also become infected with resistant Salmonella and thus pose a potential risk of Salmonella contamination of surface water and animal feeds, and consequently dissemination.     

Identification and characterization of differentially expressed ESTs of <Emphasis Type="Italic">Gossypium barbadense</Emphasis> infected by <Emphasis Type="Italic">Verticillium dahliae</Emphasis> with suppression subtractive hybridization

The wilt defense reaction of cotton is a complicated continuous process and involves a battery of genes. In this study, we adopted the suppression subtractive hybridization (SSH) technique to isolate differentially expressed ESTs from Gossypium barbadense variety 7124 during the Verticillium wilt defense process. An array of 1165 clones from the subtractive library has been screened with reverse northern blotting, of which 131 ESTs were considered as overexpressed and 16 ESTs were downregulated. Sequence analysis and blast search showed that 83 ESTs were homologous to 45 unique sequences in the databases. Among all these differentially expressed ESTs, at least three kinds of genes were characterized. The majority of ESTs with a deduced identity as aerobic metabolism enzymes were strongly expressed in the infection process. Likewise, ESTs similar to those reported for pathogen-related protein genes were also picked out in this study. These ESTs, in combination with other kinase-like genes and a defensin-like EST, constituted an assembly of genes which responded during pathogenic infection. These results imply that sea-island cotton undergoes strong oxidative stress and results in a series of defense responses when attacked by V. dahliae. To our knowledge, this is the first report on the isolation of global ESTs during the sea-island cotton defense reaction.__________From Molekulyarnaya Biologiya, Vol. 39, No. 2, 2005, pp. 214–223.Original English Text Copyright © 2005 by Zuo, Wang, Wu, Chai, Sun, Tang.This article was submitted by the authors in English.     

Purification and characterization of a novel broad-spectrum bacteriocin from Bacillus licheniformis MKU3

A bacterial strain Bacillus licheniformis MKU3, isolated from slaughterhouse sediments showed a strong antimicrobial activity. The antimicrobial substance produced by this strain was found to be a protein that inhibited a broad range of bacterial strains, such as Bacillus sp., Staphylococcus sp., Streptococcus sp., and Listeria monocytogenes. The antimicrobial peptide was purified to homogeneity by cut off membrane filtration followed by gel filtration chromatography. The purified protein with low molecular mass (< 8 kDa) was resolved as single band on Tricine SDS-PAGE. This protein was stable at 100°C for 10 min, but lost its activity at 121°C in 15 min. It was resistant to the proteolytic action of trypsin, proteinase K, and pronase E and stable within a wide range of pH (3.0∼11.0). This protein exhibited lytic activity on selected indicator strain Kurthia gibsonii GCS6.