Correlation of cellulase gene expression and cellulolytic activity throughout the gut of the termite Reticulitermes flavipes

Termites have developed cellulose digestion capabilities that allow them to obtain energy and nutrition from nutritionally poor food sources, such as lignocellulosic plant material and residues derived from it (e.g., wood and humus). Lower termites, which are equipped with both endogenous (i.e., of termite origin) and symbiotic cellulases, feed primarily on wood and wood-related materials. This study investigated cellulase gene diversity, structure, and activity in the lower termite, Reticulitermes flavipes (Kollar). We initially used a metagenomics approach to identify four genes encoding one endogenous and three symbiotic cellulases, which we refer to as Cell-1, -2, -3 and -4. These four genes encode proteins that share significant sequence similarity with known endoglucanases, exoglucanases and xylanases. Phylogenetic analyses further supported these inferred relationships by showing that each of the four cellulase proteins clusters tightly with respective termite, protozoan or fungal cellulases. Gene structure studies revealed that Cell-1, -3 and -4 are intron-free, while Cell-2 contains the first intron sequence to be identified from a termite symbiont cellulase. Quantitative real-time PCR (qRT-PCR) revealed that the endogenous Cell-1 gene is expressed exclusively in the salivary gland/foregut, whereas symbiotic Cell-2, -3, and -4 are highly expressed in the hindgut (where cellulolytic protists are harbored). Cellulase activity assays mapped the distribution pattern of endoglucanase, exoglucanase and xylanase activity throughout the R. flavipes digestive tract. Cellulase gene expression correlated well with the specific types of cellulolytic activities observed in each gut region (foregut+salivary gland, midgut and hindgut). These results suggest the presence of a single unified cellulose digestion system, whereby endogenous and symbiotic cellulases work sequentially and collaboratively across the entire digestive tract of R. flavipes.     

The difference among generations in evaluating interior lighting environment

This paper explores the difference among generations in evaluating interior lighting environment, and provides some knowledge for interior lighting design, which can accommodate all generations. Fifteen Computer Graphic pictures, which had the same dimensions (W3000 mmxH2800 mmxD6300 mm) but a different luminous environment are evaluated. Pictures are presented on a screen with a liquid crystal projector in a shaded dark room.A Semantic Differential technique with 12 subjective scales with 5 steps was used for the evaluation. Participants were chosen from 3 age groups: young, middle age, and elderly people.A difference among generations in evaluating interior lighting environment emerged. These tendencies could not be explained solely by visibility. It seems that the personal experience is closely related to the evaluation and preference of luminous environment.     

南海大鹏湾甲藻孢囊分布研究

甲藻及其它赤潮生物孢囊被认为是赤潮发生的种源,其分布特征是赤潮发生预测的重要依据。本研究对南海大鹏湾赤潮发生密集海区底泥进行了采集分析。在调查的12个站位中,共发现甲藻抱囊29种,针抱藻抱囊1种,其中以锥状斯氏藻（ScriPPsiellatrochoidea）为最优势种,多边膝沟藻（GonyaulaxPolyedra）、褐色原多甲藻（ProtoPerdiniumavellana）和塔马亚历山大藻（Alexandriumtamarense）为优势种。抱囊的水平分布以水深最深的S2和水流最缓的S4两站位抱囊的种类、数量最为丰富,且两站位的营养盐含量高于其他站位。对抱囊的垂直分布的调查显示,大多数生活抱囊集中于NP和活性磷酸盐丰富的0-5cm底泥中,5cm以下抱囊数量骤减。根据样品中各类抱囊的比例与分布特征,对大鹏湾水域抱囊形成、沉降、水底运动和分布机制进行了推测。     

湖南植物志资料（一）木兰科、八角科、五味子科、樟科、水马齿科补遗

本文报道了湖南植物新记录共计１１种,隶属于５科１０属．归并樟科植物３种２变种：将石木姜子ＬｉｔｓｅａｆａｂｅｒｉＨｅｍｓｌ．和近轮叶木姜子Ｌ．ｓｕｂｖｅｒｔｉｃｉｌｌａｔａＹａｎｇ归入黄丹木姜子Ｌ．ｅｌｏｎｇａｔａ（Ｗａｌｌ．ｅｘＮｅｅｓ）Ｂｅｎｔｈ．ｅｔＨｏｏｋ．ｆ．,将长梗绒楠ＭａｃｈｉｌｕｓｖｅｌｕｔｉｎａＣｈａｍｐ．ｅｘＢｅｎｔｈ．ｖａｒ．ｌｉｎｇｉｐｅｄｕｎｃｕｌａｔａＣ．Ｊ．Ｑｉ归入绒毛润楠Ｍ．ｖｅｌｕｔｉｎａＣｈａｍｐ．ｅｘＢｅｎｔｈ．,将短梗新木姜子ＮｅｏｌｉｔｓｅａｂｒｅｖｉｐｅｓＨ．Ｗ．Ｌｉ归入美丽新木姜子Ｎ．ｐｕｌｃｈｅｌｌａ（Ｍｅｉｓｓｎ）Ｍｅｒｒ．,将紫云山新木姜子Ｎ．ｗｕｓｈａｎｉｃａ（Ｃｈｕｎ）Ｍｅｒｒ．ｖａｒ．ｐｕｂｅｎｓＹａｎｇｅｔＰ．Ｈ．Ｈｕａｎｇ归入巫山新木姜子Ｎ．ｗｕｓｈａｎｉｃａ（Ｃｈｕｎ）Ｍｅｒｒ．．     

Macaca nigra on Bacan Island,Indonesia: Its morphology,distribution, and present habitat

We studied the monkeys inhabiting Bacan Island on the Maluku Archipelago, Indonesia. We compared them morphologically with Sulawesi black macaques (Macaca nigra).We also assessed their distribution on the island and on neighboring islands and the influence of human activity on them. We found that the Bacan black macaques are essentially similar to Sulawesi macaques; the variations in each locality are comparable. The monkeys probably inhabit the whole island or, at least, the lower forest thereon. Human activities — cultivation, logging, catching and killing monkeys — have not much affected their population. Thus they constitute a good stock of Macaca nigra,though the main population in Sulawesi is endangered.     

Three‐dimensional ultrastructure of chloroplast pockets formed under salinity stress

We investigated the invagination structure of a chloroplast that surrounds organelles such as mitochondria and peroxisomes within a thin layer of chloroplast stroma, which is called a chloroplast pocket. In this study, chloroplast pockets were observed in rice plants subjected to salinity stress but not under moderate growth condition. They included cytosol, transparent structure, lipid bodies, mitochondria, and peroxisomes. We constructed the three‐dimensional architecture of chloroplast pockets by using serial images obtained by transmission electron microscopy and focused ion beam‐scanning electron microscopy. Three types of chloroplast pockets were observed by transmission electron microscopy: Organelles were completely enclosed in a chloroplast pocket (enclosed type), a chloroplast pocket with a small gap in the middle part (gap type), and a chloroplast pocket with one side open (open type). Of the 70 pockets observed by serial imaging, 35 were enclosed type, and 21 and 14 were gap and open types, respectively. Mitochondria and peroxisomes were often in contact with the chloroplast pockets. Focused ion beam‐scanning electron microscopy revealed chloroplasts with a sheet structure partially surrounding peroxisomes. This fact suggests that chloroplasts might construct large sheet structures that would be related to the formation of chloroplast pockets.     

Mechanisms of anti-CD4-mediated depletion and immunotherapy. A study using a set of chimeric anti-CD4 antibodies

A family of rat-mouse chimeric anti-murine CD4 antibodies was used to study the mechanisms of anti-CD4-mediated depletion and immunotherapy. The chimeric antibodies retain identical affinity and specificity as the therapeutically effective prototype antibody, rat GK1.5, but are of different mouse isotypes. GK1.5 gamma 1, GK1.5 gamma 2a, and GK1.5 gamma 2b are significantly more effective at CD4+ cell depletion than rat GK1.5 when low doses of antibody are administered. In contrast, no depletion is seen with GK1.5 gamma 3 at any dose. Depletion of CD4+ cells in vivo is not correlated with either the ability of the antibody to mediate C-dependent cytotoxicity or antibody-dependent cell-mediated cytotoxicity in vitro, implying that additional antibody-mediated cytotoxic mechanisms occur in vivo. The chimeric antibodies were used to investigate the mechanism of GK1.5-mediated immunotherapy in a prototypic model of T cell-mediated autoimmunity, experimental allergic encephalomyelitis. Mice treated with a single dose of 100 micrograms of either GK1.5, GK1.5 gamma 1, or GK1.5 gamma 2a showed significant recovery within 72 h. In contrast, mice treated with 100 micrograms of GK1.5 gamma 3 showed only marginal improvement within the first 72 h and regressed within 5 days of treatment initiation. These data suggest that anti-CD4-mediated immunotherapy of murine experimental allergic encephalomyelitis is correlated with depletion of CD4+ cells.     

Production of cellulolytic enzymes from fungi and use in the saccharification of palm cake and palm fibre

Aspergillus niger ATCC 6275 possesses the highest carboxymethyl-cellulase, xylanase and -glucosidase activities under liquid and solid cultivations compared withMyceliophthora thermophila IFO 31843 and an isolate, F11. Palm cake proved to be a better substrate for enzyme production and saccharification than palm fibre. Saccharification of these two substrates, using crude enzyme solutions from three fungi and commercial enzymes, was investigated.     

Purification and Some Properties of a Fungal Lipase Preparation Used for Milk Flavouring

Intracellular lipase of a strain of Rhizopus fungus which is effective for producing a milk flavor was purified and fractionated into two components, I and II, by DEAE Sephadex A-50 column chromatography. They both proved homogeneous by electrophoresis and ultracentrifugal analysis. The sedimentation coefficient was respectively calculated to be 5.8×10^?13 for lipase I, and to be 2.2×10^?13 for lipase II. From substrate specificity, it was found that lipase I was an ordinary lipase hydrolyzing olive oil and tributyrin favourably, while, II, rather, a special lipase having a high affinity towards tricaprylin. They, also, respectively had an apparent phospholipase activity on soy-lecithin and, clearing activity on chylomicron prepared from olive oil and human serum. Their mode of action, and the effect of metals and emulsifying agents on their activity are also presented.