Epigallocatechin gallate,a major tea catechin,induces biofilm formation of <Emphasis Type="Italic">Pseudomonas syringae</Emphasis> pv. <Emphasis Type="Italic">theae</Emphasis>

Plants constitutively produce a variety of secondary metabolites that have antimicrobial activities against phytopathogens; however, interactions between these performed antimicrobial compounds and phytopathogens were poorly understood. In this study, interactions between epigallocatechin gallate (EGCg), which was a major tea catechin that had antimicrobial activities against varieties of bacteria, and Pseudomonas syringae pv. theae (P.s. theae), the causal of bacterial shoot blight of tea, were investigated. EGCg had less antimicrobial activity against P.s. theae; however, subinhibitory concentrations of EGCg induced biofilm formation. Because biofilms are induced in the presence of sucrose in the culture medium but not by P.s. theae strains deficient in exopolysaccharide levan production, biofilm induction by EGCg and levan production are closely related. EGCg increased survival of P.s. theae under dry conditions on nonwounded leaf surfaces in the presence of sucrose. These data indicate the possibility that tea catechins affect the survival of P.s. theae on the phyllosphere. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Biofilm formation and resistance to bactericides of <Emphasis Type="Italic">Pseudomonas syringae</Emphasis> pv. <Emphasis Type="Italic">theae</Emphasis>

Biofilm-grown cells of Pseudomonas syringae pv. theae (P.s.theae) wild-type strain K9301 on abiotic surface had remarkable resistance to kasugamycin in comparison to planktonically grown cells; however, the biofilm-grown cells of K9301 had the same sensitivity to copper sulfate. Because both the lesser biofilm-forming strain K9301S3 and enhanced biofilm-forming strain K9301-6 also had remarkable biofilm resistance to kasugamycin just as K9301 did and because epigallocatechin gallate, which enhanced biofilm formation of P.s.theae, had no effect on biofilm resistance to kasugamaycin, the degree of biofilm formation was not correlated with the antibiotic susceptibilities. In addition, K9301 and K9301S3 had less sensitivity to kasugamycin but had high sensitivity to copper sulfate on nonwounded leaf surfaces. These results indicate a possibility that the mechanism of P.s.theae biofilm resistance to bactericide functions on both abiotic and nonwounded leaf surfaces.     

Cloning of cDNAs encoding multiple subtypes of feline interferon-alpha from the feline epitherial cell line

Mammalian interferon (IFN)-alpha consists of a 23-amino acid signal peptide and a 166-amino acid mature protein. Feline (Fe) IFN-alpha has an extra unique molecule consisting of a 171-amino acid mature protein with a 5-amino acid insertion. We cloned eight new subtypes of cDNA encoding FeIFN- alpha from a feline epithelial cell line. Among all the FeIFN-alpha subtypes, including six that have previously been reported, the variations were found to be far less than those of IFN-alphas of other animals.     

Effects of antioxidants on induction of apoptosis in bursal cells of Fabricius during in vitro cultivation

After physically disrupting cell contacts, apoptosis of bursal cells of Fabricius was induced during in vitro cultivation. The percentage of apoptotic cells increased with incubation time and approximately 70% cells represented apoptosis after 6 hr of incubation. The induction of apoptosis was significantly inhibited by treatment of the cells with ascorbic acid (vitamin C), but not with trolox, a vitamin E analog. An intense DNA ladder pattern was shown at 6 hr post-isolation, which is a biochemical hallmark of apoptosis. Treatment of the cells with ascorbic acid inhibited the DNA fragmentation, but trolox did not. To monitor the intracellular production of reactive oxygen species (ROSs), the intensity of fluorescence emitted from DCFH-DA was measured. The intensity of fluorescence from cells incubated for 0.5-2 hr was approximately 2-fold higher than that from cells at 0 hr. The relative intensity of fluorescence decreased immediately after the addition of ascorbic acid to the cells. The intensity from the cells treated with ascorbic acid was 20-30% of that from the control cells at each incubation time. For trolox, the intensity was 50-70% of that from the control cells at each 1 to 2 hr incubation time. When ROSs-induced lipid peroxidation was assessed using cis-parinaric acid (PnA) as a monitor molecule, lipid peroxidation was found to occur in the control cells after isolation of the bursal cells. Treatment of the cells with trolox reduced lipid peroxidation, but treatment with ascorbic acid enhanced peroxidation.     

Purification of swine carbonic anhydrase isoenzyme III and measurement of its levels in tissues and plasma

The changes in the levels of carbonic anhydrase isozyme III (CA‐III) in swine plasma and urine have not been previously determined or reported. CA‐III is relatively specific to skeletal muscles, and should therefore be a useful diagnostic marker for muscle diseases. We isolated CA‐III from swine muscle tissues and determined CA‐III levels in the plasma and urine from both healthy and diseased pigs. The levels of CA‐III in the tissues of female swine (age, 3 months) and plasma of young swine (age, 1–5 months) and adult female pigs (age, 2–3 years) were determined using the ELISA system for swine CA‐III. The mean (± SD) levels of CA‐III in the skeletal muscles were 3.8 ± 3.2 mg/g (wet tissue), and in the plasma, 230 ± 193 ng/ml at 1 month, 189 ± 208 ng/ml at 2 months, 141 ± 148 ng/ml at 3 months, 78 ± 142 ng/ml at 4 months and 53 ± 99 ng/ml at 5 months. The mean level of CA‐III in the plasma samples from 2‐ to 3‐year‐old pigs was 18 ± 60 ng/ml. CA‐III in the plasma samples was found to decrease from 1 month until 3 years of age (p < 0.01). We performed far‐western blotting to clarify the cause of the observed decrease in CA‐III in plasma. Our results demonstrated that CA‐III is bound to the transferrin and albumin. In addition, we determined that the levels of CA‐III in plasma and urine samples were higher in diseased swine compared with the healthy pigs.     

Effect of growth and parturition on hair cortisol in Holstein cattle

The effect of growth and parturition on hair cortisol concentrations of cattle was investigated. Plasma, saliva, and hair (black and white from the shoulders and hip) samples were collected from calves at 6 and 24 weeks old and from dairy cattle at the dry (1 and 2 months prepartum) and lactation (10, 50, 150, and 250 days postpartum) periods. Plasma and saliva cortisol concentrations were lower in 24-week-old calves than those of 6-week-old calves, and hair cortisol concentrations decreased regardless of color and position. In 6-week-old calves, hair cortisol concentrations differed between sampling positions, but this difference was not observed in 24-week-old calves. Plasma and saliva cortisol concentrations increased before parturition until 10 days postpartum then decreased until 50 days postpartum. The same trend was observed in the cortisol concentrations of white hair. Contrarily, cortisol concentrations in black hair remained unchanged and was lower than that in white hair. Hair cortisol concentration can vary greatly depending on the location on the body, hair color, cattle age, or parturition. When this method is used, all of the above factors must be considered.     

Plant seed cystatins and their target enzymes of endogenous and exogenous origin

Cystatins are protein inhibitors of cysteine proteinases of the papain family, and those of animal origin have long been studied from medical and physiological aspects. In the meantime, oryzacystatin cloned from rice seeds in 1987 was recognized as the first well-defined cystatin of plant origin. Cloning studies followed to disclose various plant cytstatins including those of corn and soybean origin, their similarities to and differences from animal cystatins being analyzed in detail. Plant seed cystatins are now understood as factors controlling germination by inhibition of endogenous cysteine proteinases. They can also recognize insect midgut proteinases as exogenous target enzymes to control. This paper discusses chemical and phytophysiological relationships between cystatins and their targets.     

Determination of trace elements in otoliths of chum salmon Oncorhynchus keta by laser ablation-ICP-mass spectrometry

Trace element levels in the otoliths of chum salmon Oncorhynchus keta were examined by means of laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). A close linear relationship in the Sr/Ca ratios between X-ray analysis with an electron microprobe (EPMA) and LA-ICPMS analysis was found, suggesting that the latter technique could be used to distinguish the marine and freshwater life phases. Mg, Zn, Ba and Sr concentrations of the otoliths differed between the freshwater and seawater growth zones. Mg and Zn concentrations in the freshwater growth zone were significantly higher than those in the seawater growth zone, while Sr and Ba concentration s in the former were significantly lower than in the latter. The relationship between Sr concentration and Mg, Zn, and Ba concentrations at each ablation showed significant correlations. These results suggest that trace element compositions may reflect differences between freshwater and seawater environmental conditions.