Temperature-Induced Change of Chlorophyll a Forms in Phosphatidylcholine Liposomes

Absorption spectra of chlorophyll a in phosphatidylcholine liposomesat different temperatures were analyzed by a curve fitting method.The absorption spectrum was found to be composed of one majorband with a peak at 670–671 nm and minor bands with peaksat 650–652, 662–663 and 684–686 nm. Upon coolingbelow the phase transition temperature of the lipid, the componentabsorbing at 670–671 nm increased significantly at theexpense of the component absorbing at 662–663 nm. No changein the extents of other bands was observed. ¹ CIW-DPB Publication No. 795. ²On leave from the Department of Biology, Faculty of Science,Kanazawa University, Marunouchi, Kanazawa 920, Japan. (Received December 20, 1982; Accepted April 27, 1983)     

Temperature dependence of optical properties of chlorophyll a incorporated into phosphatidylcholine liposomes

Temperature-dependent spectral changes of chlorophyll a (Chl a) incorporated into liposomes of two types of phosphatidylcholine are studied. When Chl a incorporated into the liposomes is cooled down to 5°C from the temperature of the gel-to-liquid crystalline phase transition of the lipid, the red shift as well as the increase in half-bandwidth of the red peak of Chl a are only slight. By measuring the difference spectra produced by substracting the absorption spectrum at the phase transition temperature of the lipid from that at lower temperature, it is shown that the component absorbing at longer wavelength (675–685 nm) than the peak of the red maximum (about 670 nm) significantly increases at the expense of the component absorbing at shorter wavelength (657–668 nm). The positions of positive and negative peaks depend on the temperature and the molar ratio of the lipid to Chl a. The absorbance change is most pronounced on cooling below the phase transition temperature of the lipid. The temperature-induced absorbance change is almost completely reversible. The results indicate that the aggregated forms of Chl a in liposomes can be spectrophotometrically detected in the gel phase of the lipid.     

Incidence of major chromosome aberrations in 12,319 newborn infants in Tokyo

Summary In order to ascertain the frequency of chromosome aberrations among newborn infants in Japan, a chromosome survey of a large number of newborn infants is in progress. A consecutive series of 12,319 newborn babies, 6382 male and 5937 female, have been screened for clinical manifestations of autosomal aberrations and for sex chromatin and sex chromosome aberrations. Chromosome studies were carried out on 694 infants with suspected chromosome aberrations. The clinically abnormal infants were screened by conventional staining, and banding techniques have been used in the part of the study performed since 1974. Of the clincally abnormal infants, 25 had abnormal karyotypes, including two males with a 47,XXY complement, one female with a 45,X complement, three male infants with a 47,XYY complement, two with trisomy 13 syndrome, three with trisomy 18 (including one case of mosaicism), eleven with Down's syndrome (including one case of mosaicism), one with B5p partial trisomy, one with cri-du-chat syndrome, and one with Y/D translocation. The overall results are comparable to those of previous population cytogenetic studies only in the autosomal trisomies and sex chromosome abnormalities and in that the observed frequencies were comparable to those found in studies in Caucasians.To whom offprint requests should be sent     

Circulating Levels of Fatty Acid-Binding Protein Family and Metabolic Phenotype in the General Population

Objective

Fatty acid-binding proteins (FABPs) are a family of 14-15-kDa proteins, and some FABPs have been to be used as biomarkers of tissue injury by leak from cells. However, recent studies have shown that FABPs can be secreted from cells into circulation. Here we examined determinants and roles of circulating FABPs in a general population.

Methods

From the database of the Tanno-Sobetsu Study, a study with a population-based cohort design, data in 2011 for 296 subjects on no medication were retrieved, and FABP1∼5 in their serum samples were assayed.

Results

Level of FABP4, but not the other isoforms, showed a gender difference, being higher in females than in males. Levels of all FABPs were negatively correlated with estimated glomerular filtration rate (eGFR), but a distinct pattern of correlation with other clinical parameters was observed for each FABP isoform; significant correlates were alanine aminotransferase (ALT), blood pressure (BP), and brain natriuretic peptide (BNP) for FABP1, none besides eGFR for FABP2, age, BP, and BNP for FABP3, age, waist circumference (WC), BP, BNP, lipid variables, high-sensitivity C-reactive protein (hsCRP), and HOMA-R for FABP4, and age, WC, BP, ALT, BNP, and HOMA-R for FABP5. FABP4 is the most strongly related to metabolic markers among FABPs. In a multivariate regression analysis, FABP4 level was an independent predictor of HOMA-R after adjustment of age, gender, WC, BP, HDL cholesterol, and hsCRP.

Conclusions

Each FABP isoform level showed a distinct pattern of correlation with clinical parameters, although levels of all FABPs were negatively determined by renal function. Circulating FABP4 appears to be a useful biomarker for detecting pre-clinical stage of metabolic syndrome, especially insulin resistance, in the general population.     

Synthesis of fluorescent-labeled aeruginosin derivatives for high-throughput fluorescence correlation spectroscopy assays

The design and solid-phase synthesis of effective fluorescent-labeled aeruginosin derivatives and their application to the fluorescence correlation spectroscopy (FCS)-based competitive binding assay of an aeruginosin library are described. The phenolic hydroxyl group on the (R)-3-(4-hydroxyphenyl)lactic acid (d-Hpla) residue was observed to be suitable for connecting Rhodamine green derivative with minimum loss of biological activity. In addition, the FCS-based binding assay of the library using fluorescent-labeled chemical probes was also achieved.     

Photoswelling and light-inactivation of isolated chloroplasts I. Change in lipid content in light-aged chloroplasts

The formation of lipid peroxide and changes in the lipid compositionof isolated chloroplasts aged in the light or dark, were investigatedin more detail. Lipid peroxide formation was observed in thethylakoid membrane as well as in the supernatant from dark-agedchloroplasts. Light was necessary for its formation in bothsystems. We confirmed that the peroxidation of lipids formedduring aging did not induce the inhibition of photochemicalactivities in chloroplasts. Aged chloroplasts underwent decompositionof their endogeneous monogalactolipid and phosphatidylcholine(lecithin) resulting in free fatty acids and lysophosphatidylcholine(lysolecithin). Decomposition of monogalactolipid occurred inboth the light- and dark-aged chloroplasts. The change of lecithinto lysolecithin was stimulated by illumination. This suggeststhat the peroxidation of lipids occurs as a result of the illuminationof free fatty acids released from monogalactolipid and lecithinin the thylakoid membranes, and that the change of lecithinto lysolecithin is related to the inactivation of photochemicalactivities and to swelling in light-aged chloroplasts. ¹ Present address: Department of Microbiology, Ishikawa ResearchLaboratory for Public Health and Environment, Minma, Kanazawa,Japan. (Received August 15, 1974; )     

Production of D-lactic acid from defatted rice bran by simultaneous saccharification and fermentation

Production of d-lactic acid from rice bran, one of the most abundant agricultural by-products in Japan, is studied. Lactobacillus delbrueckii subsp. delbrueckii IFO 3202 and defatted rice bran powder after squeezing rice oil were used for the production. Since the rice bran contains polysaccharides as starch and cellulose, we coupled saccharification with amylase and cellulase to lactic acid fermentation. The indigenous bacteria in the rice bran produced racemic lactic acid in the saccharification at pH 6.0-6.8. Thus the pH was controlled at 5.0 to suppress the growth of the indigenous bacteria. L. delbrueckii IFO 3202 produced 28 kgm(-3) lactic acid from 100 kgm(-3) rice bran after 36 h at 37 degrees C. The yield based on the amount of sugars soluble after 36-h hydrolysis of the bran by amylase and cellulase (36 kgm(-3) from 100 kgm(-3) of the bran) was 78%. The optical purity of produced d-lactic acid was 95% e.e.     

Restoration of lysolecithin-induced inhibition of the Hill reaction in spinach chloroplasts by the addition of lecithin

Reactivation of the lysolecithin-induced inhibition of the electrontransport in spinach chloroplasts was investigated after theaddition of various molecular species of lecithin. The additionof lecithins consisting of unsaturated fatty acids to a chloroplastsuspension that previously had been incubated with lysolecithin,restored the activity of electron transport from water to ferricyanideto the level of the activity in untreated chloroplasts; andthe activity of the transport from water to dichlorophenolindophenolalso was partially restored. No reactivation of electron flowfrom water to NADP or from reduced dichlorophenolindophenolto methyl viologen was observed with any form of lecithin. Theeffect of molecular form of lecithin on the reactivation offerricyanide photoreduction in lysolecithin-incubated chloroplastswas dilinoleoyl > soybean > dioleoyl > distearoyl =dipalmitoyl lecithin. No reactivation of the Hill reaction wasobserved on the addition of dimyristoyl lecithin. The mechanismof lecithin-induced reactivation is discussed. (Received May 23, 1979; )     

Effects of a fecapentaene on protein kinase C

Protein kinase C (PKC) is a Ca2(+)- and phospholipid-dependent serine and threonine protein kinase which binds and is activated by tumor promoters such as the phorbol ester 12-0-tetradecanoylphorbol-13-acetate (TPA). PKC can be activated in vitro by phosphatidylserine (PS) plus Ca2+. We report here that the compound fecapentaene-12 can replace the requirement for PS in the activation of PKC by Ca2+. In addition, at low concentrations fecapentaene-12 can enhance the activation of PKC by Ca2+ and PS. It can also either enhance or inhibit activation of PKC by the tumor promoter teleocidin, depending on the assay conditions. These results are of interest since fecapentaene is known to be a potent mutagen that is produced by Bacteroides species present in the lumen of the human colon. The present studies raise the possibility that this compound might also play a role in colon cancer by altering the activity of PKC.