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Margo G. Haygood - One of the best experts on this subject based on the ideXlab platform.
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localization of candidatus endobugula sertula and the bryostatins throughout the life cycle of the bryozoan bugula neritina
The ISME Journal, 2007Co-Authors: Seana K Davidson, Koty H. Sharp, Margo G. HaygoodAbstract:‘Candidatus Endobugula sertula,’ the uncultivated γ-proteobacterial symbiont of the marine bryozoan Bugula neritina, synthesizes bryostatins, complex polyketides that render B. neritina larvae unpalatable to predators. Although the symbiosis is well described, little is known about the locations of ‘E. sertula’ or the bryostatins throughout larval settlement, metamorphosis and early development. In this study, we simultaneously localized ‘E. sertula’ and the bryostatins in multiple stages of the B. neritina life cycle, using a novel bryostatin detection method based on its known ability to bind mammalian protein kinase C. Our results suggest that the bryostatins are deposited onto the exterior of B. neritina larvae during embryonic development, persist on the larval surface throughout metamorphosis and are shed prior to cuticle formation. During metamorphosis, ‘E. sertula’ remains adhered to the larval pallial epithelium and is incorporated into the preancestrula cystid tissue layer, which ultimately develops into a bud and gives rise to the next zooid in the colony. Colocalization of bryostatin signal with aggregates of ‘E. sertula’ in buds of ancestrulae suggested new synthesis of bryostatins in ancestrulae. In adult B. neritina colonies, symbiont microcolonies were observed in the funicular cords of rhizoids, which likely result in asexual transmission of ‘E. sertula’ to regenerated colonies. Furthermore, bryostatin signal was detected on the surface of the rhizoids of adult B. neritina colonies. Through simultaneous localization of the bryostatins and the ‘E. sertula,’ we determined how ‘E. sertula’ is transmitted, and identified shifts in bryostatin localization throughout the life cycle of the host B. neritina.
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identification of the putative bryostatin polyketide synthase gene cluster from candidatus endobugula sertula the uncultivated microbial symbiont of the marine bryozoan bugula neritina
Journal of Natural Products, 2007Co-Authors: Sebastian Sudek, Christine Anderson, Nicole B. Lopanik, Laura E Waggoner, Mark Hildebrand, Haibin Liu, Amrish Patel, David H Sherman, Margo G. HaygoodAbstract:The bryostatins are protein kinase C modulators with unique structural features and potential anticancer and neurological activities. These complex polyketides were isolated from the marine bryozoan Bugula neritina, but recent studies indicate that they are produced by the uncultured symbiotic bacterium "Candidatus Endobugula sertula" ("E. sertula"). Here we present the putative biosynthetic genes: five modular polyketide synthase (PKS) genes, a discrete acyltransferase, a beta-ketosynthase, a hydroxy-methyl-glutaryl CoA synthase (HMG-CS), and a methyltransferase. The cluster was sequenced in two closely related "E. sertula" strains from different host species. In one strain the gene cluster is contiguous, while in the other strain it is split into two loci, with one locus containing the PKS genes and the other containing the accessory genes. Here, we propose a hypothesis for the biosynthesis of the bryostatins. Thirteen PKS modules form the core macrolactone ring, and the pendent methyl ester groups are added by the HMG-CS gene cassette. The resulting hypothetical compound bryostatin 0 is the common basis for the 20 known bryostatins. As "E. sertula" is to date uncultured, heterologous expression of this biosynthetic gene cluster has the potential of producing the bioactive bryostatins in large enough quantities for development into a pharmaceutical.
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identification of the putative bryostatin polyketide synthase gene cluster from candidatus endobugula sertula the uncultivated microbial symbiont of the marine bryozoan bugula neritina
Journal of Natural Products, 2007Co-Authors: Sebastian Sudek, Christine Anderson, Nicole B. Lopanik, Laura E Waggoner, Mark Hildebrand, Haibin Liu, Amrish Patel, David H Sherman, Margo G. HaygoodAbstract:The bryostatins are protein kinase C modulators with unique structural features and potential anticancer and neurological activities. These complex polyketides were isolated from the marine bryozoan Bugula neritina, but recent studies indicate that they are produced by the uncultured symbiotic bacterium “Candidatus Endobugula sertula” (“E. sertula”). Here we present the putative biosynthetic genes: five modular polyketide synthase (PKS) genes, a discrete acyltransferase, a β-ketosynthase, a hydroxy-methyl-glutaryl CoA synthase (HMG-CS), and a methyltransferase. The cluster was sequenced in two closely related “E. sertula” strains from different host species. In one strain the gene cluster is contiguous, while in the other strain it is split into two loci, with one locus containing the PKS genes and the other containing the accessory genes. Here, we propose a hypothesis for the biosynthesis of the bryostatins. Thirteen PKS modules form the core macrolactone ring, and the pendent methyl ester groups are ad...
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brya an unusual modular polyketide synthase gene from the uncultivated bacterial symbiont of the marine bryozoan bugula neritina
Chemistry & Biology, 2004Co-Authors: Mark Hildebrand, Christine Anderson, Sebastian Sudek, Laura E Waggoner, Haibin Liu, David H Sherman, Scott Allen, Margo G. HaygoodAbstract:"Candidatus Endobugula sertula," the uncultivated bacterial symbiont of Bugula neritina, is the proposed source of the bryostatin family of anticancer compounds. We cloned a large modular polyketide synthase (PKS) gene complex from "Candidatus Endobugula sertula" and characterized one gene, bryA, which we propose is responsible for the initial steps of bryostatin biosynthesis. Typical PKS domains are present. However, acyltransferase domains are lacking in bryA, and beta-ketoacyl synthase domains of bryA cluster with those of PKSs with discrete, rather than integral, acyltransferases. We propose a model for biosynthesis of the bryostatin D-lactate starter unit by the bryA loading module, utilizing atypical domains homologous to FkbH, KR, and DH. The bryA gene product is proposed to synthesize a portion of the pharmacologically active part of bryostatin and may be useful in semisynthesis of clinically useful bryostatin analogs.
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candidatus endobugula glebosa a specific bacterial symbiont of the marine bryozoan bugula simplex
Applied and Environmental Microbiology, 2004Co-Authors: Grace E Lim, Margo G. HaygoodAbstract:The bryozoans Bugula neritina and Bugula simplex harbor bacteria in the pallial sinuses of their larvae as seen by electron microscopy. In B. neritina, the bacterial symbiont has been characterized as a gamma-proteobacterium, “Candidatus Endobugula sertula.” “Candidatus E. sertula” has been implicated as the source of the bryostatins, polyketides that provide chemical defense to the host and are also being tested for use in human cancer treatments. In this study, the bacterial symbiont in B. simplex larvae was identified by 16S rRNA-targeted PCR and sequencing as a gamma-proteobacterium closely related to and forming a monophyletic group with “Candidatus E. sertula.” In a fluorescence in situ hybridization, a 16S ribosomal DNA probe specific to the B. simplex symbiont hybridized to long rod-shaped bacteria in the pallial sinus of a B. simplex larva. The taxonomic status “Candidatus Endobugula glebosa” is proposed for the B. simplex larval symbiont. Degenerate polyketide synthase (PKS) primers amplified a gene fragment from B. simplex that closely matched a PKS gene fragment from the bryostatin PKS cluster. PCR surveys show that the symbiont and this PKS gene fragment are consistently and uniquely associated with B. simplex. Bryostatin activity assays and chemical analyses of B. simplex extracts reveal the presence of compounds similar to bryostatins. Taken together, these findings demonstrate a symbiosis in B. simplex that is similar and evolutionarily related to that in B. neritina.
Seana K Davidson - One of the best experts on this subject based on the ideXlab platform.
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localization of candidatus endobugula sertula and the bryostatins throughout the life cycle of the bryozoan bugula neritina
The ISME Journal, 2007Co-Authors: Seana K Davidson, Koty H. Sharp, Margo G. HaygoodAbstract:‘Candidatus Endobugula sertula,’ the uncultivated γ-proteobacterial symbiont of the marine bryozoan Bugula neritina, synthesizes bryostatins, complex polyketides that render B. neritina larvae unpalatable to predators. Although the symbiosis is well described, little is known about the locations of ‘E. sertula’ or the bryostatins throughout larval settlement, metamorphosis and early development. In this study, we simultaneously localized ‘E. sertula’ and the bryostatins in multiple stages of the B. neritina life cycle, using a novel bryostatin detection method based on its known ability to bind mammalian protein kinase C. Our results suggest that the bryostatins are deposited onto the exterior of B. neritina larvae during embryonic development, persist on the larval surface throughout metamorphosis and are shed prior to cuticle formation. During metamorphosis, ‘E. sertula’ remains adhered to the larval pallial epithelium and is incorporated into the preancestrula cystid tissue layer, which ultimately develops into a bud and gives rise to the next zooid in the colony. Colocalization of bryostatin signal with aggregates of ‘E. sertula’ in buds of ancestrulae suggested new synthesis of bryostatins in ancestrulae. In adult B. neritina colonies, symbiont microcolonies were observed in the funicular cords of rhizoids, which likely result in asexual transmission of ‘E. sertula’ to regenerated colonies. Furthermore, bryostatin signal was detected on the surface of the rhizoids of adult B. neritina colonies. Through simultaneous localization of the bryostatins and the ‘E. sertula,’ we determined how ‘E. sertula’ is transmitted, and identified shifts in bryostatin localization throughout the life cycle of the host B. neritina.
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evidence for the biosynthesis of bryostatins by the bacterial symbiont candidatus endobugula sertula of the bryozoan bugula neritina
Applied and Environmental Microbiology, 2001Co-Authors: Seana K Davidson, Scott W Allen, Christine Anderson, Margo G. HaygoodAbstract:The marine bryozoan, Bugula neritina, is the source of the bryostatins, a family of macrocyclic lactones with anticancer activity. Bryostatins have long been suspected to be bacterial products. B. neritina harbors the uncultivated gamma proteobacterial symbiont “Candidatus Endobugula sertula.” In this work several lines of evidence are presented that show that the symbiont is the most likely source of bryostatins. Bryostatins are complex polyketides similar to bacterial secondary metabolites synthesized by modular type I polyketide synthases (PKS-I). PKS-I gene fragments were cloned from DNA extracted from the B. neritina-“E. sertula” association, and then primers specific to one of these clones, KSa, were shown to amplify the KSa gene specifically and universally from total B. neritina DNA. In addition, a KSa RNA probe was shown to bind specifically to the symbiotic bacteria located in the pallial sinus of the larvae of B. neritina and not to B. neritina cells or to other bacteria. Finally, B. neritina colonies grown in the laboratory were treated with antibiotics to reduce the numbers of bacterial symbionts. Decreased symbiont levels resulted in the reduction of the KSa signal as well as the bryostatin content. These data provide evidence that the symbiont E. sertula has the genetic potential to make bryostatins and is necessary in full complement for the host bryozoan to produce normal levels of bryostatins. This study demonstrates that it may be possible to clone bryostatin genes from B. neritina directly and use these to produce bryostatins in heterologous host bacteria.
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identification of sibling species of the bryozoan bugula neritina that produce different anticancer bryostatins and harbor distinct strains of the bacterial symbiont candidatus endobugula sertula
The Biological Bulletin, 1999Co-Authors: Seana K Davidson, Margo G. HaygoodAbstract:Although the cosmopolitan marine bryozoan Buga chemotype M lacks bryostatins with the octa-2,4- dienoate substituent. B. neritina contains a symbiotic y-pro- teobacterium "Cundidutus Endobugula sertula," and it has been proposed that bryostatins may be synthesized by bac- terial symbionts. In this study, B. neritina populations along the California coast were sampled for genetic variation and bryostatin content. Colonies that differ in chemotype also differ genetically by 8% in the mitochondrial cytochrome c oxidase subunit 1 (CO I) gene; this difference is sufficient to suggest that the chemotypes represent different species. Each species contains a distinct strain of "E. sertula" that differs at four nucleotide sites in the small subunit ribo- somal RNA (SSU rRNA) gene. These results indicate that the chemotypes have a genetic basis rather than an environ- mental cause. Gene sequences from an Atlantic sample matched sequences from the California chemotype M col- onies, suggesting that this type may be cosmopolitan due to transport on boat hulls.
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small subunit rrna genes and in situ hybridization with oligonucleotides specific for the bacterial symbionts in the larvae of the bryozoan bugula neritina and proposal of candidatus endobugula sertula
Applied and Environmental Microbiology, 1997Co-Authors: Margo G. Haygood, Seana K DavidsonAbstract:Larvae of the bryozoan Bugula neritina harbor bacterial symbionts. These symbionts were identified as a novel species of gamma-proteobacterium, based on ribosomal small-subunit rRNA gene sequences. In situ hybridization with oligonucleotides specific for the symbiont confirmed the origin of the sequence. The taxonomic status "Candidatus Endobugula sertula" is proposed for the larval symbiont.
Bastida-zavala Rolando - One of the best experts on this subject based on the ideXlab platform.
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Figure 6 from: Bastida-Zavala R (2012) Serpula and SpiraSerpula (Polychaeta, Serpulidae) from the Tropical Western Atlantic and Gulf of Guinea. ZooKeys 198: 1-23. https://doi.org/10.3897/zookeys.198.3030
2012Co-Authors: Bastida-zavala RolandoAbstract:Figure 6 - Distribution of Serpula madrigalae sp. n., Serpula vossae sp. n., and Serpula cf. vermicularis
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Figure 5 from: Bastida-Zavala R (2012) Serpula and SpiraSerpula (Polychaeta, Serpulidae) from the Tropical Western Atlantic and Gulf of Guinea. ZooKeys 198: 1-23. https://doi.org/10.3897/zookeys.198.3030
2012Co-Authors: Bastida-zavala RolandoAbstract:Figure 5 - Exploratory analysis of the number of opercular radii and body length ratio: Serpula madrigalae sp. n. (n= 1, only for reference), Serpula vossae sp. n. (n= 7), and Serpula cf. vermicularis (n= 4)
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Serpula and SpiraSerpula (Polychaeta, Serpulidae) from the Tropical Western Atlantic and Gulf of Guinea
2012Co-Authors: Bastida-zavala RolandoAbstract:Six species of Serpula and SpiraSerpula were identified, mainly, from the material of the expeditions of the Rosenstiel School of Marine and Atmospheric Science, University of Miami, including two new species of Serpula. Serpula madrigalae sp. n. from the Turks and Caicos has a tube with five longitudinal ridges, four rows of alveoli and a medium-sized shallow symmetrical opercular funnel with 17 radii, and an inner surface with opercular tubercles. Serpula vossae sp. n. from the Western Caribbean and Bahamas has a tube with 6–8 longitudinal ridges, and a large, deep symmetrical opercular funnel, with 21–33 radii, and a smooth inner surface. Serpula cf. vermicularis, recorded from the Gulf of Guinea (tropical eastern Atlantic), is distinguished from the nominal species in possessing fewer opercular radii (33–39) and the lack of a proximal rasp in the bayonet chaetae; tubes are missing. The distribution range is extended for the three known SpiraSerpula species found in the collections, S. caribensis, S. karpatensis and S. ypsilon
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Figure 4 from: Bastida-Zavala R (2012) Serpula and SpiraSerpula (Polychaeta, Serpulidae) from the Tropical Western Atlantic and Gulf of Guinea. ZooKeys 198: 1-23. https://doi.org/10.3897/zookeys.198.3030
2012Co-Authors: Bastida-zavala RolandoAbstract:Figure 4 - A–J Serpula vossae sp. n., from Honduras, USNM 1157004, holotype A tube B entire body; from Guatemala, UMML 22.1053 C–D tube and detail of peristome; from Bahamas, UMML 22.435 E collar region; from Cuba, IO F radiole with eggs; from Honduras, USNM 1157004, holotype G bayonet chaetae H operculum; from Guatemala, UMML 22.1053 I operculum; from Bahamas, UMML 22.435 J operculum
Nicole B. Lopanik - One of the best experts on this subject based on the ideXlab platform.
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latitudinal variation of a defensive symbiosis in the bugula neritina bryozoa sibling species complex
PLOS ONE, 2014Co-Authors: Jonathan Linneman, Grace Limfong, Darcy Paulus, Nicole B. LopanikAbstract:Mutualistic relationships are beneficial for both partners and are often studied within a single environment. However, when the range of the partners is large, geographical differences in selective pressure may shift the relationship outcome from positive to negative. The marine bryozoan Bugula neritina is a colonial invertebrate common in temperate waters worldwide. It is the source of bioactive polyketide metabolites, the bryostatins. Evidence suggests that an uncultured vertically transmitted symbiont, “Candidatus Endobugula sertula”, hosted by B. neritina produces the bryostatins, which protect the vulnerable larvae from predation. Studies of B. neritina along the North American Atlantic coast revealed a complex of two morphologically similar sibling species separated by an apparent biogeographic barrier: the Type S sibling species was found below Cape Hatteras, North Carolina, while Type N was found above. Interestingly, the Type N colonies lack “Ca. Endobugula sertula” and, subsequently, defensive bryostatins; their documented northern distribution was consistent with traditional biogeographical paradigms of latitudinal variation in predation pressure. Upon further sampling of B. neritina populations, we found that both host types occur in wider distribution, with Type N colonies living south of Cape Hatteras, and Type S to the north. Distribution of the symbiont, however, was not restricted to Type S hosts. Genetic and microscopic evidence demonstrates the presence of the symbiont in some Type N colonies, and larvae from these colonies are endowed with defensive bryostatins and contain “Ca. Endobugula sertula”. Molecular analysis of the symbiont from Type N colonies suggests an evolutionarily recent acquisition, which is remarkable for a symbiont thought to be transmitted only vertically. Furthermore, most Type S colonies found at higher latitudes lack the symbiont, suggesting that this host-symbiont relationship is more flexible than previously thought. Our data suggest that the symbiont, but not the host, is restricted by biogeographical boundaries.
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identification of the putative bryostatin polyketide synthase gene cluster from candidatus endobugula sertula the uncultivated microbial symbiont of the marine bryozoan bugula neritina
Journal of Natural Products, 2007Co-Authors: Sebastian Sudek, Christine Anderson, Nicole B. Lopanik, Laura E Waggoner, Mark Hildebrand, Haibin Liu, Amrish Patel, David H Sherman, Margo G. HaygoodAbstract:The bryostatins are protein kinase C modulators with unique structural features and potential anticancer and neurological activities. These complex polyketides were isolated from the marine bryozoan Bugula neritina, but recent studies indicate that they are produced by the uncultured symbiotic bacterium "Candidatus Endobugula sertula" ("E. sertula"). Here we present the putative biosynthetic genes: five modular polyketide synthase (PKS) genes, a discrete acyltransferase, a beta-ketosynthase, a hydroxy-methyl-glutaryl CoA synthase (HMG-CS), and a methyltransferase. The cluster was sequenced in two closely related "E. sertula" strains from different host species. In one strain the gene cluster is contiguous, while in the other strain it is split into two loci, with one locus containing the PKS genes and the other containing the accessory genes. Here, we propose a hypothesis for the biosynthesis of the bryostatins. Thirteen PKS modules form the core macrolactone ring, and the pendent methyl ester groups are added by the HMG-CS gene cassette. The resulting hypothetical compound bryostatin 0 is the common basis for the 20 known bryostatins. As "E. sertula" is to date uncultured, heterologous expression of this biosynthetic gene cluster has the potential of producing the bioactive bryostatins in large enough quantities for development into a pharmaceutical.
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identification of the putative bryostatin polyketide synthase gene cluster from candidatus endobugula sertula the uncultivated microbial symbiont of the marine bryozoan bugula neritina
Journal of Natural Products, 2007Co-Authors: Sebastian Sudek, Christine Anderson, Nicole B. Lopanik, Laura E Waggoner, Mark Hildebrand, Haibin Liu, Amrish Patel, David H Sherman, Margo G. HaygoodAbstract:The bryostatins are protein kinase C modulators with unique structural features and potential anticancer and neurological activities. These complex polyketides were isolated from the marine bryozoan Bugula neritina, but recent studies indicate that they are produced by the uncultured symbiotic bacterium “Candidatus Endobugula sertula” (“E. sertula”). Here we present the putative biosynthetic genes: five modular polyketide synthase (PKS) genes, a discrete acyltransferase, a β-ketosynthase, a hydroxy-methyl-glutaryl CoA synthase (HMG-CS), and a methyltransferase. The cluster was sequenced in two closely related “E. sertula” strains from different host species. In one strain the gene cluster is contiguous, while in the other strain it is split into two loci, with one locus containing the PKS genes and the other containing the accessory genes. Here, we propose a hypothesis for the biosynthesis of the bryostatins. Thirteen PKS modules form the core macrolactone ring, and the pendent methyl ester groups are ad...
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isolation of two polyketide synthase gene fragments from the uncultured microbial symbiont of the marine bryozoan bugula neritina
Applied and Environmental Microbiology, 2006Co-Authors: Nicole B. Lopanik, Nancy M Targett, Niels LindquistAbstract:"Candidatus Endobugula sertula," the uncultured microbial symbiont of the bryozoan Bugula neritina, produces ecologically and biomedically important polyketide metabolites called bryostatins. We isolated two gene fragments from B. neritina larvae that have high levels of similarity to polyketide synthase genes. These gene fragments are clearly associated with the symbiont and not with the host.
Dini Farahvian - One of the best experts on this subject based on the ideXlab platform.
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Pengaruh Konsentrasi FeCl3 dan Lama Inkubasi Terhadap Hasil Degradasi Lignoselulosa Ampas Tebu (Bagasse) dengan Menggunakan Jamur Serpula lacrymans.
2016Co-Authors: Dini FarahvianAbstract:Ampas tebu (bagasse) merupakan limbah agroindustri yang ketersediaannya melimpah dan mengandung lignoselulosa, yang tidak hanya berpotensi diubah menjadi energi (bioenergi) namun juga diubah menjadi bahan kimia khusus (biochemical). Proses awal yang harus dilakukan adalah degradasi lignoselulosa atau pretreatment yang berpengaruh pada penurunan atau peningkatan kadar selulosa, hemiselulosa dan lignin. Pretreatment biologi dengan menggunakan jamur pelapuk coklat Serpula lacrymans dipilih karena memiliki kelebihan pada proses degradasi tidak hanya mendepolimerisasi lignin namun dapat merepolimerisasinya, sehingga masih dapat dimanfaatkan sebagai bahan biochemical. Hydroxyl radical (*OH) yang diperoleh dari reaksi Fenton (Fe2+ + H2O2 Fe3+ + *OH + OH-) pada sistem degradasi lignoselulosa oleh jamur pelapuk coklat, berperan untuk degradasi lignoselulosa. Keberlangsungan reaksi Fenton tergantung pada sistem regenerasi hydrogen peroksida (H2O2) dan mekanisme reduksi Fe3+ kembali ke Fe2+. Sumber Fe3+ didapatkan dari bahan secara terbatas, sehingga dilakukan penambahan Fe3+ untuk meningkatkan hasil degradasi lignoselulosa. Inkubasi selama 35 hari dapat menunjukkan pola hasil degradasi lignoselulosa dengan menggunakan jamur Serpula lacrymans. Oleh karena itu, dilakukan penelitian untuk mengetahui pengaruh penambahan Fe3+ dan lama inkubasi terhadap hasil degradasi lignoselulosa pada proses pretreatment ampas tebu (bagasse) dengan menggunakan jamur Serpula lacrymans. Percobaan dilakukan dengan menggunakan Rancangan Faktorial dengan factor konsentrasi FeCl3 (0, 10, 20, 30, 40 dan viii 50 μM) dan lama inkubasi (0, 7, 14, 21, 28 dan 35 hari). Hasil proses pretreatement yang telah diberi perlakuan penambahan FeCl3 dan lama inkubasi dilihat dari nilai pH, Total Soluble Phenol (TSP), Total Gula Reduksi (TGR) dan susut berat. Hasil analisis data ragam MANOVA menunjukkan tidak terjadi interaksi antara penambahan FeCl3 dan lama inkubasi berdasarkan nilai pH, TSP, TGR dan susut berat. Tidak terdapat interaksi antara perlakuan penambahan FeCl3 dan lama inkubasi terhadap nilai TSP, TGR, pH dan susut berat. Hasil degradasi terbaik berdasarkan persentase peningkatan nilai TSP tertinggi diperoleh dari kombinasi perlakuan penambahan FeCl3 0 μM dan lama inkubasi 21 hari, dengan nilai TSP sebesar 0,270 mg/gr bahan atau meningkat sebesar 176,37%. Nilai TGR pada kombinasi perlakuan tersebut sebesar 86,756 mg/gr bahan atau meningkat sebesar 56,05%. Nilai pH pada kombinasi perlakuan tersebut sebesar 4,5 atau menurun sebesar 32,16%. Nilai susut berat pada kombinasi tersebut sebesar 17,955%
