The major goal of this study was to achieve sustained cultivation of virulent T. pallidum in vitro. The putatuive binding of host proteins to the outer membrane (OM) of intact, virulent T. pallidum subsp. pallidum has been investigated. A major breakthrough was the development of a filtration assay, usinglow protein-binding membrane filters, for the measurement of substances bound to or incorporated into th eOM of T. pallidum. This avoided the conventional manipulations which can damage the fragile OM of T. pallidum. Using this filtration assay, studies on the binding of host serum proteins demonstrated that intact treponemes did not bind host proteins as previously reported. It also indicated that previous studies were probably performed with damaged by this research. The studies on the binding of polyclonal and monoclonal antibodies to intact and detergent treated treponemes provided evidence of the low level binding of antibody to intact treponemes which was greatly enhanced but the removal of the outer membrane with 0.1% Triton X. This research research corroborated that of others which suggests that the outer membrane of T. pallidum contains very little protein or surface exposed antigen.

In order to understand and manipulate carbon flux to sucrose one needs to consider not only its biosynthetic pathways, but also the competing sinks for carbon in various parts of the plant and at different stages of development. The cell wall and sucrose is known to be the major sinks for carbon in young and mature tissues of sugarcane. UDP-Glucose is a central metabolite in the synthesis of both sucrose and most of the cell wall polysaccharides (including cellulose, hemicellulose and pectic polymers) and manipulation of the flux into either of the cell wall components could therefore cause an increase of flux toward one or more of the competing sinks. In the present study UDP-Glucose dehydrogenase (UGD) activity was chosen for down regulation as it catalyzes the rate limiting step in the biosynthesis of the precursors of both hemicellulose and pectin, a major competing sink for assimilated carbon. Transgenic sugarcane lines with repressed UGD activity showed significantly increased sucrose accumulation in all internodes which was highly correlated with reduced UGD activity. Sucrose phosphate synthase had increased activation which suggests an alteration in carbon flux toward sucrose. The reduction of carbon flux through UGD was compensated for by an increase in the activity of the myo-inositol oxygenation pathway (MIOP), an alternative pathway for the synthesis of cell wall matrix precursors. The increased activity of the MIOP resulted in increased total uronic acids and pentoses in the cell wall. Total cell wall glucose was also increased which is a further indication of altered carbon metabolism.

Thesis (PhD(Agric) (Horticulture))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: Mealiness, a soft, dry textural disorder of ‘Forelle’ pear (Pyrus communis L.), is a problem for the South African fruit export industry. Soft, dry textural disorders seem to be related to changes in cell wall breakdown. The aim of this work was, therefore, to investigate the occurrence of mealiness‐associated changes in the cell wall and elucidate the mechanism by which mealiness occurs in ‘Forelle’ pear, as well as to characterise cell wall changes occurring during normal ripening. Mealy ‘Forelle’ tissues had significantly lower total galacturonic acids associated with the middle lamella (water‐ and CDTA‐soluble fractions). The water‐soluble pectin of mealy tissues was depolymerised at an earlier stage of ripening. The widespread disintegration of cell‐to‐cell adhesion in mealy cell walls only, suggests that the middle lamella and the plasmodesmata are more broken down. In mealy ‘Forelle’ tissues there was no indication of less broken down high molecular weight polyuronides in the CDTA fraction, normally associated with these dry, soft textures. The pectins from mealy tissues were more broken down and both mealy and non‐mealy tissue polyuronides depolymerised. Furthermore, there was a lack of light toluidine staining in the larger air spaces, which would indicate such water‐insoluble pectins. These data suggest that the formation of high molecular weight pectate gels is unlikely in mealy ‘Forelle’ pear. The slight increase in the galactose content in mealy tissues in CDTA‐ and Na2CO3‐soluble fractions and slight decrease in the 1 M KOH glycan fraction during later stages of ripening (6+11, 9+7, 9+11; weeks at ‐0.5°C plus days at 15°C) may indicate that galactose loosely interlinked into the glycan fraction broke down sooner for mealy tissues. This didn’t increase molecular size profiles in the CDTA fraction. Arabinose content was slightly higher in the 4 M KOH fraction and slightly lower in mealy tissues of water‐ and CDTA fractions. This did not influence the molecular weight of the glycans compared to those in the nonmealy tissues. ‘Forelle’ data therefore seem to be more congruent with a decrease in intercellular adhesion as the mechanism by which mealiness occurs, rather than the formation of high molecular weight pectins taking up the cellular fluid. ‘Forelle’ pear water‐soluble pectin content increases with increased ripening. High amounts of watersoluble pectin and low amounts of Na2CO3‐soluble pectin suggests that solubilisation of rhamnogalacturonan‐I pectins must have taken place during early ripening (at a fruit firmness of > 4.7 kg (7.9mm tip). Galactose and glucose in the pectin fraction dramatically decreased after fruit ripened to a firmness of 4.5 kg, whereafter they remained unchanged. This was also the period in which fruit softened the most and the biggest increase in pectin water‐solubility occurred. It is not known whether these events are coincidental, or linked causally. Rhamnose and arabinose extractability increased in the water fraction and xylose, fucose and mannose increased in glycan fractions with ripening. The biggest changes in polyuronide solubilisation and depolymerisation occurred in water‐ and CDTA fractions between storage and ripening durations of 3+7 (4.7 kg) and 6+4 (2.7 kg). / AFRIKAANSE OPSOMMING: Melerigheid, ʼn sagte droë tekstuur afwyking van ‘Forelle’ pere (Pyrus communis L.), is ʼn probleem vir die Suid Afrikaanse vrugte uitvoerbedryf. Sagte, droë tekstuur afwykings blyk betrekking te hê op selwandafbraak veranderinge. Die doel van die studie was dus om die melerigheid‐geassosieerde veranderinge in die selwand te ondersoek, sowel as om vas te stel wat die meganisme betrokke is by melerigheid ontwikkeling in ‘Forelle’ pere. Die selwand veranderinge gedurende normale rypwording is ook gekarakteriseer. Melerige ‘Forelle’ weefsel het betekenisvol laer totale galakturoonsuur wat geassosieer is met die middellamella (water‐ en CDTA‐oplosbare fraksies). Die water‐oplosbare pektien van melerige weefsel was op ʼn vroeër stadium van rypwording gedepolimeriseer. Die wydverspreide disintegrasie van sel‐tot‐sel adhesie, slegs in melerige selwande, dui aan dat die middellamella en die plasmodesmata meer afgebreek is. Daar is geen indikasie van hoë molekulêre massa poliuroniedes in die CDTA fraksie van melerige ‘Forelle’ weefsel, wat gewoonlik geassosieer word met droë, sagte teksture nie. Die pektiene van melerige weefsel was meer afgebreek en melerige en nie‐melerige weefsel se poliurone was gedepolimeriseer. Daar was ook geen ligte toluïdien verkleuring in die groter intersellulêre lugruimtes nie, wat ʼn aanduiding sou wees van wateronoplosbare pektiene. Hierdie data dui dus aan dat die vorming van hoë molekulêre pektien jel in melerige ‘Forelle’ pere onwaarskynlik is. Die klein toename in galaktose inhoud in die CDTA‐ en Na2CO3‐ oplosbare fraksies en ʼn klein afname in 1 M KOH glikaan fraksie tydens latere rypheidstadiums (6+11, 9+7, 9+11; weke by ‐0.5°C plus dae by 15°C), kan beteken dat los verweefde galaktose in die glikaan fraksie vroeër afgebreek het in melerige weefsels. Die molekulêre grootte profiel is nie verander in die CDTA fraksie nie. Arabinose inhoud was bietjie hoër in die 4 M KOH fraksie en bietjie laer in melerige weefsel van die water‐ en CDTA fraksies. Die molekulêre massa van die glikane was klaarblyklik onbeïnvloed hierdeur. ‘Forelle’ data blyk dus meer saam te stem met die meganisme waar ʼn vermindering in intersellulêre adhesie ʼn rol speel in melerigheid, eerder as die meganisme waar hoë molekulêre pektien selvloeistowwe bind. ‘Forelle’ peer water‐oplosbare pektieninhoud neem toe met toenemende rypheid. Hoë vlakke wateroplosbare pektien en lae vlakke Na2CO3‐oplosbare pektien stel voor dat die oplossing van rhamnogalakturonan‐I pektiene gedurende vroeë rypwording moes plaasgevind het (by ʼn fermheid van > 4.7 kg (7.9mm punt). Galaktose en glukose in die pektienfraksie het drasties verminder nadat vrugte tot ʼn fermheid van 4.5 kg ryp geword het, waarna hul onveranderd gebly het. Dit was ook die periode waarin vrugte die meeste sag geword het en die grootste toename in poliuronied wateroplosbaarheid gevind is. Dit is nie bekend of die gebeure toevallig of oorsaaklik verbind is nie. Rhamnose en arabinose ekstraheerbaarheid het vermeerder in die water fraksies, en xylose, fukose en mannose het vermeerder in die glikaan fraksies gedurende rypwording. Die grootste verandering in oplosbaarheid en depolimerisasie het plaasgevind in die water‐ en CDTA fraksies tussen opberging en rypwordingsperiodes van 3+7 (4.7 kg) en 6+4 (2.7 kg).

Many Gram-positive and Gram-negative bacteria produce an additional thick layer of carbohydrate polymers on the cell wall surface. These capsules (capsular polysaccharides; CPS) play critical roles in interactions between bacteria and their environments (Whitfield, 2006). This is especially important in infection processes since for both Gram-negative and Gram-positive pathogens CPS is the point of first contact with the host immune system (Whitfield, 2006). However, the details of CPS biosynthesis and assembly mechanisms are still unclear. Therefore, we embarked on structural and kinetic studies of the proteins Wzc, Wza and Wzb/ Cps4B from the Wzy-dependent pathway, as well as the protein WbdD from the ATP-binding cassette (ABC) transporter dependent system. Full-length Wzc failed to crystallise due to the presence of large disordered regions and the overall difficulty of membrane protein crystallisation. A truncated version of Wzc (1-480) without the C-terminal tyrosine kinase domain was crystallised and diffracted to 15 Å in house. A previous study suggested Wza and Wzc form a functional complex (Whitfield, 2006), so Wza was also studied. Since the full-length Wza structure is available (C. Dong et al., 2006), Pulsed electron–electron double resonance spectroscopy (PELDOR) was used to study the conformational change. The PELDOR spectroscopy distance fingerprint of Wza was determined. These data also confirmed that PELDOR is a powerful tool to study large, highly symmetrical membrane proteins and can be used to study other complex membrane protein systems, such as ion channels or transporters. The crystal structure of Wzb the cognate phosphatase of Wzc was determined to 2.2 Å. Also Cps4B, which is a functional homologue of Wzb but has a completely unrelated sequence, was crystallised in two crystal forms. Form I and II Cps4B crystals diffracted to 2.8 Å and 1.9 Å resolution in house, respectively. The full-length WbdD failed to crystallise due to the presence of large disordered regions. Therefore, a shorter construct, WbdD₅₅₆ (1-556) was cloned and crystallised. The structure was determined to 2.2 Å. WbdD is a bifunctional enzyme consisting of a methyltransferase (MTase) and a kinase domain. In order to better understand the function of this protein, a variety of techniques were used, such as the ADP-Glo kinase assay, Nuclear magnetic resonance (NMR) spectroscopy, small angle X-ray scattering (SAXS) and X-ray crystallography. The various findings in the current projects provide meaningful insights towards a better understanding of the CPS biosynthesis and assembly mechanisms, which may contribute to a more intensive study identifying inhibitors and beginning to unravel the mechanism of chain length regulation.

The physiological role of the teichoic acid polymers found in Gram-positive bacterial cell walls is not known. Studies of Bacillus subtilis hybrid strains implicate a defined chromosomal region, which includes the tag-1 locus, as necessary for teichoic acid biosynthesis. A set of ten mutants carrying lesions in this region was identified from among forty-four temperature-sensitive (ts) mutants generated by nitrosoguanidine mutagenesis and bacteriophage 029 selection. This protocol gave a population enriched for ts, versus auxotrophic, mutants. For each of the ten mutants, the frequency of genetic reconstruction, or correction, of the ts phenotype indicated that it was due to change(s) in a single gene. Results of two-factor transformation crosses sorted the mutants into three complementation groups; all ten could complement tag-1. Mutants in two complementation groups were transformed to ts⁺ with cloned rodC DNA. The map order of the newly isolated ts markers was determined from the results of two factor crosses. Orientation with respect to the hisA marker was inferred from transduction experiments. The newly isolated strains were shown to be conditional rod⁻ mutants. Growth at 48°C resulted in reduced growth rates and spherically shaped cells. Additional phenotypes seen for some mutants, namely 029 phage resistance and ts spore outgrowth, appeared closely associated with the ts rod⁻ mutation. Wall phosphate content for two of the mutants, following growth at 48°C, was found to be reduced in comparison to the wild-type control. Taken together these results lend support to the argument that the tag-1 region of the chromosome, which most likely directs teichoic acid biosynthesis, is important for establishment and maintenance of the normal bacillary morphology seen for B. subtilis. The importance of other gene products to the organization of newly synthesized wall was examined using B. subtilis macrofibers. Left- and right-handed macrofibers were converted to spheroplasts and the multi-celled structures regenerated under the two sets of conditions conducive for production of the original, and inverse hand. The helix hands observed for the regenerated structures always corresponded to those expected on the basis of the parental genotype.

Plants colonised land 460 million years ago and charophytes represent the closest living relatives of land plants. The ability to live on land may depend on the presence of certain cell wall polysaccharides such as xyloglucan, a hemicellulose exclusively found in land plants (Popper and Fry, 2003). The cell walls of charophytes are poorly characterised. The aim of this project was to use biochemical techniques to characterise the cell wall polysaccharides of charophytic algae in relation to early land plant phylogeny. Hydrolysis of Coleochaete scutata and Chara vulgaris cell walls in 2 M trifluoroacetic acid yielded predominantly GalA, Gal, Glc and Man residues and also some Ara, Xyl and traces of Fuc and Rha. In addition, hydrolysis of Chara pectin revealed an abundance of an unusual monosaccharide, 3-O-methyl-D-galactose, which was structurally identified by a series of 1-D and 2D NMR spectroscopy by COSY, TOCSY, NOESY and HSQC. 3-O-Methyl-D-galactose is more commonly found in lycophyte cell walls where its presence has been suggested to be related to lycophytes’ evolutionarily isolated position (Popper et al., 2001). The newly discovered presence of 3-O-methyl-D-galactose in charophyte pectin suggests that this polymer may be more complex than previously thought. Coleochaete and Chara hemicellulose extracts were fractionated by anion-exchange chromatography into five classes. A strongly anionic fraction from Chara hemicellulose was found to be rich in Glc, Xyl, Gal and Fuc suggestive of a xyloglucan-like polysaccharide. However, XEG was unable to produce diagnostic xyloglucan oligosaccharides in either Coleochaete or Chara hemicelluloses. Xylanase and mannanase digestion of Coleochaete and Chara hemicelluloses gave xylan- and mannan-oligosaccharides. Furthermore, lichenase digestion of Coleochaete hemicellulose yielded an unusual octasaccharide composed of approximately equimolar xylose and glucose. My work has shown that charophyte cell walls are a source of undiscovered monosaccharides and potentially novel pectic and hemicellulosic domains which may have important functions in enabling the successful colonisation of land by plants.

Les β-1,2 oligomannosides (β-Mans), dont la présence est relativement rare dans le monde vivant, font partie des facteurs de C. albicans contribuant à sa virulence. Ils sont retrouvés dans la paroi de la levure associés aux N-glycannes d’un haut polymère de mannoses lié à un peptide, le phosphopeptidomannane (PPM) et des mannoprotéines (MPs) ainsi qu’à la copule glycannique d’un glycolipide de la famille des mannose-inositol-phosphocéramides, le phospholipomannane (PLM). Les mécanismes de reconnaissance des β-Mans par l’hôte dépendent du degré de polymérisation des oligomannosides et des molécules qui les portent. Une famille de 9 enzymes, les β-1,2 mannosyltransférases (Bmts), permettent la biosynthèse des β-Mans de C. albicans. Ces enzymes ont des fonctions distinctes car leur activité a une spécificité assez stricte qui dépend du glycoconjugué et de l’étape de β-mannosylation. Le travail présenté dans cette thèse s’est appuyé sur la spécificité des Bmts, principalement celles initiant la biosynthèse des β-Mans (Bmt1: N-mannanes acido stables – Bmt2: N-mannanes acido labiles – Bmt5: PLM) pour définir i) le rôle respectif des β-Mans dans la virulence de C. albicans et ii) la contribution des différents glycoconjugués dans l’expression de surface des β-Mans. Une grande partie de l’étude a reposé sur la génération de doubles mutants (bmt1bmt2δ) et (bmt2bmt5δ) exprimant des β-Mans uniquement sur une fraction ou un type de glycoconjugué et d'un triple mutant (bmt1bmt2bmt5δ) n’exprimant plus de β-Mans. Nous avons tout d’abord réévalué la β-mannosylation des MPs qui était jusqu’à présent déduite de celle du PPM. En analysant les O-mannosides des mutants bmtsδ, nous avons pu mettre en évidence l’implication de Bmt1 et Bmt3, qui ajoutent respectivement le 1er et le 2ème β-mannose, dans la O-mannosylation des MPs. L’analyse de la β-mannosylation des MPs et d’une protéine recombinante chez le mutant bmt1δ a mis en évidence le rôle essentiel de Bmt1 dans ce processus. L’analyse en immunofluorescence des différents mutants a montré que seul le PPM et les MPs sont responsables de l’expression de surface des β-Mans. Cette expression a un impact inattendu sur la virulence dans des modèles murins de candidoses disséminées. Les souches exprimant des β-Mans en surface sont en effet moins virulentes que les mutants présentant des défauts de β-Mannosylation. Les mutants, principalement bmt1bmt2bmt5δ sont néanmoins moins virulents chez des souris n’exprimant plus la galectine 3, lectine reconnaissant les β-Mans. Ces résultats montrent le double rôle des β-Mans selon leur localisation et le conjugué qui les porte: d’une part ils permettent à l’hôte d’éliminer la levure via la galectine 3 et d’autre part ils peuvent contribuer à sa virulence via certainement le PLM. La β-mannosylation du PLM est indispensable pour l’activité inflammatoire du PLM sur les macrophages et sa modulation peut entraîner la résistance de la levure à certains antifongiques. La régulation de la β-mannosylation de ses glycoconjugués est un moyen pour C. albicans de s’adapter à différentes conditions. La β-mannosylation du PPM et des MPs est réduite à 37°C et lorsque le pH diminue, pouvant ainsi permettre à la levure d’être moins reconnue in vivo et d’échapper aux mécanismes de défense de l’hôte. Nous avons pu également mettre en évidence un mécanisme permettant à C. albicans de changer de sérotype en inactivant Bmt1. Ce mécanisme qui n’est pas encore parfaitement décrit, permet à la levure de mieux coloniser le tube digestif de souris. Nos résultats mettent ainsi en évidence d’une part l’expression complexe des β-Mans dans la paroi de C. albicans et leur rôle dans la virulence en fonction de leur localisation et d’autre part l’adaptation de la levure à différents environnements. / Β-1,2 oligomannosides (β-Mans) are rare in the living world and are considered as factors contributing to C. albicans virulence. They are present in the cell wall associated to N-glycans of a high mannose polymer linked to a peptide, the phosphopeptidomannan (PPM) and to mannoproteins (MPs) and they are part of the glycan moiety of a glycolipid from the mannose-inositol-phosphoceramid family, the phospholipomannan (PLM). Recognition of β-Mans by the host depends on their polymerization degree and molecules they are associated to. A family of nine enzymes, β-1,2 mannosyltransferases (Bmts), is involved in β-Mans biosynthesis of C. albicans. These enzymes have distinct functions with specificities of substrate and step of β-mannosylation. According to these specificities, especially for initiation of β-Mans biosynthesis (Bmt1: acid stable N-mannan- Bmt2: acid labile N-mannan- Bmt5: PLM), the thesis project was designed to define i) the respective role of β-Mans in C. albicans virulence and ii) the contribution of the different cell wall glycoconjugates in β-Mans surface expression. Double mutants (bmt1bmt2δ and bmt2bmt5δ) expressing β-Mans only on a fraction or a type of glycoconjugate and a triple mutant (bmt1bmt2bmt5δ) expressing no more β-Mans have been generated. We have first reassessed MPs β-mannosylation which was originally deduced from the PPM one. After analysis of O-mannosides from bmtsδ mutants, we have evidenced that Bmt1 and Bmt3 are involved in MPs O-mannosylation by adding the first and the second β-mannose, respectively. β-mannosylation of both MPs and a recombinant protein in bmt1δ mutant was checked and we evidenced an essential role of Bmt1 in this process. Immunofluorescence assays using the different mutants revealed that PPM and MPs are responsible for β-Mans surface expression. Expression of β-Mans at the cell surface had an unexpected impact on virulence in two murine models of disseminated candidiasis. Strains expressing superficial β-Mans were less virulent than mutants with β-mannosylation defects. These mutants, mainly bmt1bmt2bmt5δ, were nevertheless less virulent in mice which do not express galectin-3, lectin that binds β-Mans. These results show different biologic properties of β-Mans depending on their localization and the conjugate they are associated to: they can enable yeast clearance via galectin 3 but they can also contribute to virulence certainly via PLM. PLM β-mannosylation is essential for the glycolipid inflammatory activities in macrophages and its modulation can lead to yeast resistance to some antifungals. Regulation of glycoconjugates β-mannosylation enables C. albicans to adapt to different conditions. PPM and MPs β-mannosylation is reduced at 37°C and at lower pH, which can help C. albicans to counteract host defense in vivo as it is then less recognized by galectin 3. We have also evidenced a mechanism by which C. albicans can switch serotype after Bmt1 inactivation. This mechanism, not completely described, allows the yeast to better colonize the murine digestive tract. Our results highlight both the complex expression of β-Mans in C. albicans cell wall and their role in virulence according to their localization and the adaptation of the yeast to different environments.

Wood from coniferous trees is an important source of renewable biomass. It can contribute to provision of carbon neutral energy, biomaterials and housing for a growing population. Softwood is mainly composed of cellulose, galactoglucomannan, xylan and lignin. This thesis focuses on the biosynthesis and function of Glucuronic acid (GlcA) decorations on softwood xylan. Results demonstrate that this GUX (GlucUronic acid substitution of Xylan)-dependent xylan branching is critical for the maintenance of biomass recalcitrance in a model vascular plant Arabidopsis thaliana. Experiments employing in vitro and in planta activity assays show that conifer transcriptomes encode at least two distinct GUX enzymes which are active glucuronosyltransferases. Interestingly, these enzymes have different specific activities, with one adding evenly spaced GlcA branches and the other one being able to add consecutive decorations. It is possible that these different patterns of xylan branching may have an impact on ability of xylan to interact with cellulose fibrils. To investigate the role for xylan binding to cellulose, Arabidopsis mutant plants in which this interaction is lost were evaluated alongside transgenic mutant lines in which the interaction may be restored. Results of this analysis indicate that the presence of cellulose-bound xylan might have an influence on plant vasculature integrity and thus it may have an effect on plant growth and biomass properties. Moreover, further results indicate that some xylan cellulose interaction is likely to occur in cell wall macrofibrils which can be detected in softwood. Taken together, this thesis provides insights into the process of conifer xylan glucuronidation and the possible role these branches may be playing in the maintenance of softwood recalcitrance and mechanical properties. In addition to identifying potential mutagenesis targets for improving softwood processing, this work is a proof of concept for the use of GUX enzymes for in vivo and in vitro biosynthesis of novel xylan structures with potential industrial application.

Plant cell walls compose the largest source of sugars on earth and are a potential source after conversion for liquid transportation fuels. However, the crystalline region of cellulose and the lignin that incases it present significant obstacles for enzymes to digest. This lowers the sugar yield, which ultimately decreases the production efficiency of bioethanol. A pretreatment that could help lowering the amount of crystallinity; meanwhile, breakdown the matrix of lignin and polysaccharides that cover cellulose fibers would be ideal. Here we propose a physical pretreatment strategy of electron beam irradiation that could potentially decrease cellulose crystallinity as well as unzip the lignin structure. Four types of biomass: cellulose, yellow pine, yellow poplar, and switchgrass were irradiated with a 12 MeV electron beam (Sterigenics, Inc.) at dosages of 0, 54, 80, 148 and 403 kGy. By combining the result from the wet chemical analysis of percent weight glucose/ cellulose from the HPLC, percent crystallinity from the Wide Angle X-Ray Diffraction (WAX) and the change of chemical functionality from Fourier Transform Infrared Spectrometer (FTIR), a promising effect is obtained in pine and yellow poplar but not in cellulose and switchgrass. A significant increase in percent glucose is observed for pine at higher doses as shown by (r = 0.97, P< 0.0076) which are 9.4 and 27% at 0 and 403 kGy. The amount of glucose considerably changes from all different types of biomass over time (P< 0.0001). A strong correlation of decreasing in percent crystallinity was found in poplar (r = -0.89, P< 0.05) from 32.4% to 17.4% and related to an average increase in percent glucose produced from 30 to 55% comparing between 0 and 403 kGy.

No description available.