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1.
Felipe Cava Aurelio Hidalgo José Berenguer 《Extremophiles : life under extreme conditions》2009,13(2):213-231
Thermus spp is one of the most wide spread genuses of thermophilic bacteria, with isolates found in natural as well as in man-made
thermal environments. The high growth rates, cell yields of the cultures, and the constitutive expression of an impressively
efficient natural competence apparatus, amongst other properties, make some strains of the genus excellent laboratory models
to study the molecular basis of thermophilia. These properties, together with the fact that enzymes and protein complexes
from extremophiles are easier to crystallize have led to the development of an ongoing structural biology program dedicated
to T. thermophilus HB8, making this organism probably the best so far known from a protein structure point view. Furthermore, the availability
of plasmids and up to four thermostable antibiotic selection markers allows its use in physiological studies as a model for
ancient bacteria. Regarding biotechnological applications this genus continues to be a source of thermophilic enzymes of great
biotechnological interest and, more recently, a tool for the over-expression of thermophilic enzymes or for the selection
of thermostable mutants from mesophilic proteins by directed evolution. In this article, we review the properties of this
organism as biological model and its biotechnological applications. 相似文献
2.
From 42 different hot springs in six provinces belonging to distinct geographical regions of Turkey, 451 thermophilic bacilli
were isolated and 67 isolates with a high amylase activity were selected to determine the α-glucosidase production capacities
by using pNPG as a substrate. α-Glucosidase production capacities of the isolates varied within the range from 77.18 to 0.001 U/g. Eleven
of our thermophilic bacilli produced α-glucosidase at significant levels comparable with that of the reference strains tested;
thus, five strains, F84b (77.18 U/g), A333 (48.64 U/g), F84a (36.64 U/g), E134 (32.09 U/g), and A343 (10.79 U/g), were selected
for further experiments. 16S rDNA sequence analysis revealed that these selected isolates all belonged to thermophilic bacilli
16S rDNA genetic group 5, four of them representing the genus Geobacillus, while strain A343 had an uncultured bacterium as the closest relative. Changes in α-glucosidase levels in the intracellular
and extracellular fractions were determined during 48-h cultivation of A333, A343, F84a, F84b, E134, and the reference strain
G. stearothermophilus ATCC 12980. According to α-glucosidase production type and enzyme levels in intracellular and extracellular fractions, Geobacillus spp. A333, F84a, and F84b were defined as extracellular enzyme producers, whereas the thermophilic bacterium A343 was found
to be an intracellular α-glucosidase producer, similar to ATCC 12980 strain. Geobacillus sp. E134 differed in α-glucosidase production type from all tested isolates and the reference strain; it was described as
a membrane-associated cell-bound enzyme producer. In this study, apart from screening a great number of new thermophilic bacilli
from the hot springs of Turkey, which have not yet been thoroughly studied, five new thermostable α-1,4-glucosidase-producing
bacilli that have biotechnological potential with α-glucosidases located at different cell positions were obtained.
The text was submitted by the authors in English. 相似文献
3.
Henne A Brüggemann H Raasch C Wiezer A Hartsch T Liesegang H Johann A Lienard T Gohl O Martinez-Arias R Jacobi C Starkuviene V Schlenczeck S Dencker S Huber R Klenk HP Kramer W Merkl R Gottschalk G Fritz HJ 《Nature biotechnology》2004,22(5):547-553
Thermus thermophilus HB27 is an extremely thermophilic, halotolerant bacterium, which was originally isolated from a natural thermal environment in Japan. This organism has considerable biotechnological potential; many thermostable proteins isolated from members of the genus Thermus are indispensable in research and in industrial applications. We present here the complete genome sequence of T. thermophilus HB27, the first for the genus Thermus. The genome consists of a 1,894,877 base pair chromosome and a 232,605 base pair megaplasmid, designated pTT27. The 2,218 identified putative genes were compared to those of the closest relative sequenced so far, the mesophilic bacterium Deinococcus radiodurans. Both organisms share a similar set of proteins, although their genomes lack extensive synteny. Many new genes of potential interest for biotechnological applications were found in T. thermophilus HB27. Candidates include various proteases and key enzymes of other fundamental biological processes such as DNA replication, DNA repair and RNA maturation. 相似文献
4.
New bacilli from shallow hydrothermal vents of Panarea Island (Italy) and their biotechnological potential 总被引:1,自引:0,他引:1
Aims: To characterize bacilli isolated from shallow hydrothermal vents of Panarea Island (Italy) and evaluate their biotechnological potential. Methods and Results: Fifteen isolates were characterized by culture and molecular methods. Eleven isolates were thermophilic, six isolates were alkalophilic and four of them were haloalkalophilic. After 16S rRNA gene sequencing, four strains, exhibiting sequence similarity below 95% with deposited strains, may represent novel species of bacilli. One strain was strictly related to Geobacillus subterraneus, but shared phenotypic characteristics for which it could be considered a new strain of this species. Four strains were affiliated with different Bacillus spp. Most isolates produced gelatinase, lipases and amylase, and some were mercury tolerant. Exopolysaccharides (EPS) production was tested adding different sugars (glucose, sucrose, trehalose, fructose, ribose, xylose and mannose, 1% w/v) as a carbon source in a minimal medium. The highest EPS yield (185 mg l?1) was reached by strain 1A70 utilizing ribose as a carbon source. Conclusions: Novel strains of Geobacillus and indigenous ribotypes of Bacillus with biotechnological potential inhabit shallow vents of Panarea Island. Significance and Impact of the Study: New strains of thermophilic bacilli from Panarea are producers of useful biomolecules for industrial purposes as well as environmental and biotechnological applications. 相似文献
5.
Raja Noor Zaliha Raja Abd Rahman Thean Chor Leow Abu Bakar Salleh Mahiran Basri 《BMC microbiology》2007,7(1):77
Background
Thermophilic Bacillus strains of phylogenetic Bacillus rRNA group 5 were described as a new genus Geobacillus. Their geographical distribution included oilfields, hay compost, hydrothermal vent or soils. The members from the genus Geobacillus have a growth temperatures ranging from 35 to 78°C and contained iso-branched saturated fatty acids (iso-15:0, iso-16:0 and iso-17:0) as the major fatty acids. The members of Geobacillus have similarity in their 16S rRNA gene sequences (96.5–99.2%). Thermophiles harboring intrinsically stable enzymes are suitable for industrial applications. The quest for intrinsically thermostable lipases from thermophiles is a prominent task due to the laborious processes via genetic modification. 相似文献6.
Balwinder Singh Sooch Baljinder Singh Kauldhar Munish Puri 《Bioprocess and biosystems engineering》2016,39(11):1759-1773
A newly isolated microbial strain of thermophilic genus Geobacillus has been described with emphasis on polyphasic characterization and its application for degradation of hydrogen peroxide. The validation of this thermophilic strain of genus Geobacillus designated as BSS-7 has been demonstrated by polyphasic taxonomy approaches through its morphological, biochemical, fatty acid methyl ester profile and 16S rDNA sequencing. This thermophilic species of Geobacillus exhibited growth at broad pH and temperature ranges coupled with production of extraordinarily high quantities of intracellular catalase, the latter of which as yet not been reported in any member of this genus. The isolated thermophilic bacterial culture BSS-7 exhibited resistance against a variety of organic solvents. The immobilized whole cells of the bacterium successfully demonstrated the degradation of hydrogen peroxide (H2O2) in a packed bed reactor. This strain has potential application in various analytical and diagnostic methods in the form of biosensors and biomarkers in addition to applications in the textile, paper, food and pharmaceutical industries. 相似文献
7.
Cihan Arzu Coleri Ozcan Birgul Tekin Nilgun Cokmus Cumhur 《World journal of microbiology & biotechnology》2011,27(11):2683-2696
The phylogenetic diversity of 31 thermophilic bacilli belonging to genera Geobacillus and Aeribacillus were investigated which were isolated from various geothermal sites of Turkey. Twenty-seven of these isolates were found
to be belonged within the genus Geobacillus, whereas 4 of them were identified as Aeribacillus pallidus. The comparative 16S rRNA gene sequence analyses revealed that the A. pallidus isolates displayed sequence similarity values from 98.0 to 99.6% to their closest relative. Furthermore, Geobacillus isolates showed sequence similarity values from 88.9 to 99.8% with the reference type strains. According to the phylogenetic
analysis, isolates belonging to genus Geobacillus were diverged into nine clusters and among these isolates, 19 of them were identified as strains related to G. caldoproteolyticus, G. thermodenitrificans, G. stearothermophilus, G. thermoglucosidasius and G. toebii with the most abundant 13 isolates from G.
caldoproteolyticus. Four of the Geobacillus isolates were named as unidentified mix group, as they found to be genetically very homogenous like their closely related
type species: G. thermoleovorans, G. vulcani, G. lituanicus, G. kaustophilus, G. caldovelox, G. caldotenax, and G. uralicus. Moreover, the sequence comparisons of E173a, E265, C161ab and A142 isolates demonstrated that they represented novel species
among genus Geobacillus as they shared lower than 96.7% sequence similarity to all the described type species. The AluI-, HaeIII- and TaqI-ARDRA results were in congruence with the 16S rRNA gene sequence analyses. By ARDRA results, the isolates were able to be
differentiated and clustered, the discriminative restriction fragments of these isolates and type species were determined
and the novelty of E173, E265, C161ab and A142 isolates could be displayed. Some differentiating phenotypic characters and
the ability of amylase, glucosidase and protease production of these bacilli were also studied and biotechnologically valuable
thermostable enzyme producing isolates were introduced in order to use in further studies. 相似文献
8.
Bijender Singh 《Critical reviews in biotechnology》2016,36(1):59-69
Myceliophthora thermophila syn. Sporotrichum thermophile is a ubiquitous thermophilic mould with a strong ability to degrade organic matter during optimal growth at 45?°C. Both genome analysis and experimental data have suggested that the mould is capable of hydrolyzing all major polysaccharides found in biomass. The mould is able to secrete a large number of hydrolytic enzymes (cellulases, laccases, xylanases, pectinases, lipases, phytases and some other miscellaneous enzymes) employed in various biotechnological applications. Characterization of the biomass-hydrolyzing activity of wild and recombinant enzymes suggests that this mould is highly efficient in biomass decomposition at both moderate and high temperatures. The native enzymes produced by the mould are more efficient in activity than their mesophilic counterparts beside their low enzyme titers. The mould is able to synthesize various biomolecules, which are used in multifarious applications. Genome sequence data of M. thermophila also supported the physiological data. This review describes the biotechnological potential of thermophilic mould, M. thermophila supported by genomic and experimental evidences. 相似文献
9.
Background
Members of the thermophilic genus Geobacillus can grow at high temperatures and produce a battery of thermostable hemicellulose hydrolytic enzymes, making them ideal candidates for the bioconversion of biomass to value-added products. To date the molecular determinants for hemicellulose degradation and utilization have only been identified and partially characterized in one strain, namely Geobacillus stearothermophilus T-6, where they are clustered in a single genetic locus.Results
Using the G. stearothermophilus T-6 hemicellulose utilization locus as genetic marker, orthologous hemicellulose utilization (HUS) loci were identified in the complete and partial genomes of 17/24 Geobacillus strains. These HUS loci are localized on a common genomic island. Comparative analyses of these loci revealed extensive variability among the Geobacillus hemicellulose utilization systems, with only seven out of 41–68 proteins encoded on these loci conserved among the HUS+ strains. This translates into extensive differences in the hydrolytic enzymes, transport systems and metabolic pathways employed by Geobacillus spp. to degrade and utilize hemicellulose polymers.Conclusions
The genetic variability among the Geobacillus HUS loci implies that they have variable capacities to degrade hemicellulose polymers, or that they may degrade distinct polymers, as are found in different plant species and tissues. The data from this study can serve as a basis for the genetic engineering of a Geobacillus strain(s) with an improved capacity to degrade and utilize hemicellulose.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-836) contains supplementary material, which is available to authorized users. 相似文献10.
Application of rpoB sequence similarity analysis, REP-PCR and BOX-PCR for the differentiation of species within the genus Geobacillus 总被引:1,自引:0,他引:1
Meintanis C Chalkou KI Kormas KA Lymperopoulou DS Katsifas EA Hatzinikolaou DG Karagouni AD 《Letters in applied microbiology》2008,46(3):395-401
Aim: To investigate the applicability of rpoB gene, which encodes the β subunit of RNA polymerase, to be used as an alternative to 16S rRNA for sequence similarity analysis in the thermophilic genus Geobacillus. Rapid and reproducible repetitive extragenic palindromic fingerprinting techniques (REP‐ and BOX‐polymerase chain reaction) were also used. Methods and Results: rpoB DNA (458 bp) were amplified from 21 Geobacillus‐ and Bacillus type strains, producing different BOX‐ and REP‐PCR profiles, in addition to 11 thermophilic isolates of Geobacillus and Bacillus species from a Santorini volcano habitat. The sequences and the phylogenetic tree of rpoB were compared with those obtained from 16S rRNA gene analysis. The results demonstrated between 90–100% (16S rRNA) and 74–100% (rpoB) similarity among examined bacteria. Conclusion: BOX‐ and REP‐PCR can be applied for molecular typing within Geobacillus genus. rpoB sequence similarity analysis permits a more accurate discrimination of the species within the Geobacillus genus than the more commonly used 16S rRNA. Significance and Impact of the Study: The obtained results suggested that rpoB sequence similarity analysis is a powerful tool for discrimination between species within the ecologically and industrially important strains of Geobacillus genus. 相似文献
11.
12.
Zambare VP Bhalla A Muthukumarappan K Sani RK Christopher LP 《Extremophiles : life under extreme conditions》2011,15(5):611-618
A recently discovered thermophilic isolate, Geobacillus sp. R7, was shown to produce a thermostable cellulase with a high hydrolytic potential when grown on extrusion-pretreated
agricultural residues such corn stover and prairie cord grass. At 70°C and 15–20% solids, the thermostable cellulase was able
to partially liquefy solid biomass only after 36 h of hydrolysis time. The hydrolytic capabilities of Geobacillus sp. R7 cellulase were comparable to those of a commercial cellulase. Fermentation of the enzymatic hydrolyzates with Saccharomyces cerevisiae ATCC 24860 produced ethanol yields of 0.45–0.50 g ethanol/g glucose with more than 99% glucose utilization. It was further
demonstrated that Geobacillus sp. R7 can ferment the lignocellulosic substrates to ethanol in a single step that could facilitate the development of a
consolidated bioprocessing as an alternative approach for bioethanol production with outstanding potential for cost reductions. 相似文献
13.
Edwin van Bloois Daniel E. Torres Pazmiño Remko T. Winter Marco W. Fraaije 《Applied microbiology and biotechnology》2010,86(5):1419-1430
DyP-type peroxidases comprise a novel superfamily of heme-containing peroxidases which is unrelated to the superfamilies of
known peroxidases and of which only a few members have been characterized in some detail. Here, we report the identification
and characterization of a DyP-type peroxidase (TfuDyP) from the thermophilic actinomycete Thermobifida fusca. Biochemical characterization of the recombinant enzyme showed that it is a monomeric, heme-containing, thermostable, and
Tat-dependently exported peroxidase. TfuDyP is not only active as dye-decolorizing peroxidase as it also accepts phenolic compounds and aromatic sulfides. In fact,
it is able to catalyze enantioselective sulfoxidations, a type of reaction that has not been reported before for DyP-type
peroxidases. Site-directed mutagenesis was used to determine the role of two conserved residues. D242 is crucial for catalysis
while H338 represents the proximal heme ligand and is essential for heme incorporation. A genome database analysis revealed
that DyP-type peroxidases are frequently found in bacterial genomes while they are extremely rare in other organisms. Most
of the bacterial homologs are potential cytosolic enzymes, suggesting metabolic roles different from dye degradation. In conclusion,
the detailed biochemical characterization reported here contributes significantly to our understanding of these enzymes and
further emphasizes their biotechnological potential. 相似文献
14.
I-Son Ng Chen-Wei Li Yi-Fang Yeh Po Ting Chen Jiun-Ly Chir Chin-Hua Ma Su-May Yu Tuan-hua David Ho Chii-Gong Tong 《Extremophiles : life under extreme conditions》2009,13(3):425-435
A thermophilic Geobacillus bacterium secreting high activity of endo-glucanase (EC 3.2.1.4) was isolated from rice straw compost supplemented with pig
manure. A full-length gene of 1,104 bp, celA, encoding this glycosyl hydrolase family 5 endo-glucanase of 368 amino acids was isolated. No related gene from Geobacillus has been reported previously. The recombinant CelA expressed in Escherichia coli had an optimal activity at 65°C and pH 5.0, and it exhibited tenfold greater specific activity than the commercially available
Trichoderma reesei endo-glucanase. CelA displayed activity over a broad temperature range from 45 to 75°C and was a thermostable enzyme with
90% activity retained after heating at 65°C for 6 h. Interestingly, CelA activity could be enhanced by 100% in the presence
of 2 mM MnSO4. CelA had high specific activity over β-d-glucan from barley and Lichenan, making it a potentially useful enzyme in biofuel and food industries. 相似文献
15.
Audrius Bubinas Gražina Giedraitytė Lilija Kalėdienė Ona Nivinskiene Rita Butkiene 《Central European Journal of Biology》2008,3(1):61-68
A number of thermophilic bacteria capable of utilizing naphthalene as a sole source of carbon were isolated from a high-temperature
oilfield in Lithuania. These isolates were able to utilize several other aromatic compounds, such as anthracene, benzene,
phenol, benzene-1, 3-diol, protocatechuic acid as well. Thermophilic isolate G27 ascribed to Geobacillus genus was found to have a high aromatic compound degrading capacity. Spectrophotometric determination of enzyme activities
in cell-free extracts revealed that the last aromatic ring fission enzyme in naphthalene biotransformation by Geobacillus sp. G27 was inducible via protocatechuate 3, 4-dioxygenase; no protocatechuate 4, 5-dioxygenase, protocatechuate 2, 3-dioxygenase activities were detected.
Intermediates such as o-phthalic and protocatechuic acids detected in culture supernatant confirmed that the metabolism of
naphthalene by Geobacillus sp. G27 can proceed through protocatechuic acid via ortho-cleavage pathway and thus differs from the pathways known for mesophilic bacteria. 相似文献
16.
Anna Derekova Rossica Mandeva Margarita Kambourova 《World journal of microbiology & biotechnology》2008,24(9):1697-1702
Phylogenetic diversity of culturable bacteria from genus Bacillus and related genera, isolated from 18 Bulgarian hot springs was investigated in association with their functional diversity.
Sixty-seven thermophilic and facultative thermophilic strains were isolated under aerobic conditions at 60°C. Sixty-six of
them belonged to eight species in four genera from Bacillus group: Anoxybacillus, Geobacillus, Brevibacillus and Bacillus. Representatives of the genus Anoxybacillus predominated. Based on phylogenetic analysis (<97% sequence similarity) four strains belonged to groups representing potentially
novel species. Producers of carbohydrases, degrading 12 from the tested 13 substrates were isolated. About half of the isolates
degraded amylose by exo- or endo-mechanism of action of their enzymes. The isolates degrading hemicellulose carbohydrates
like arabinan, arabinoxylan, β-glucan, galactan, galactomannan and xyloglucan were reached to. Some of the microorganisms
were able to uptake microbial polysaccharides like curdlan and gellan and their enzymes were between first reported thermostable
enzymes in their groups, like gellan lyase and curdlan lyase A relation between species affiliation and their functional activity
was observed—all A. gonensis strains were producer of amylolytic enzymes, most of Brevibacillus ruber strains were able to grow in a minimal medium with xanthan. 相似文献
17.
Daniel Valenzuela-Heredia Carlos Henríquez-Castillo Raúl Donoso Paris Lavín Michael T. Ringel Thomas Brüser José Luis Campos 《Microbial biotechnology》2021,14(3):1060-1072
Members of the genus Pseudomonas inhabit diverse environments, such as soil, water, plants and humans. The variability of habitats is reflected in the diversity of the structure and composition of their genomes. This cosmopolitan bacterial genus includes species of biotechnological, medical and environmental importance. In this study, we report on the most relevant genomic characteristics of Pseudomonas sp. strain ABC1, a siderophore-producing fluorescent strain recently isolated from soil. Phylogenomic analyses revealed that this strain corresponds to a novel species forming a sister clade of the recently proposed Pseudomonas kirkiae. The genomic information reveals an overrepresented repertoire of mechanisms to hoard iron when compared to related strains, including a high representation of fecI-fecR family genes related to iron regulation and acquisition. The genome of the Pseudomonas sp. ABC1 contains the genes for non-ribosomal peptide synthetases (NRPSs) of a novel putative Azotobacter-related pyoverdine-type siderophore, a yersiniabactin-type siderophore and an antimicrobial betalactone; the last two are found only in a limited number of Pseudomonas genomes. Strain ABC1 can produce siderophores in a low-cost medium, and the supernatants from cultures of this strain promote plant growth, highlighting their biotechnological potential as a sustainable industrial microorganism. 相似文献
18.
Hyperthermophilic archaea with unique biochemical and physiological characteristics are important organisms for fundamental research of life science and have great potential for biotechnological applications. However, low transformation efficiency of foreign DNA molecules impedes developments in genetic modification tools and industrial applications. In this study, we applied prolonged overlap extension PCR (POE-PCR) to generate multimeric DNA molecules and then transformed them into two hyperthermophilic archaea, Thermococcus kodakarensis KOD1 and Pyrococcus yayanosii A1. This study was the first example to demonstrate the enhanced transformation efficiencies of POE-PCR products by a factor of approximately 100 for T. kodakarensis KOD1 and 8 for P. yayanosii A1, respectively, relative to circular shuttle plasmids. Furthermore, directed evolution of a modestly thermophilic enzyme, Methanothermococcus okinawensis 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), was conducted to obtain more stable ones due to high transformation efficiency of T. kodakarensis (i.e. ~3 × 104 CFU per μg DNA). T. kodakarensis harbouring the most thermostable MoHMGR mutant can grow in the presence of a thermostable antibiotic simvastatin at 85°C and even higher temperatures. This high transformation efficiency technique could not only help develop more hyperthermophilic enzyme mutants via directed evolution but also simplify genetical modification of archaea, which could be novel hosts for industrial biotechnology. 相似文献
19.
Casey M. Theriot Sherry R. Tove Amy M. Grunden 《Applied microbiology and biotechnology》2010,86(1):177-188
Prolidases hydrolyze the unique bond between X-Pro dipeptides and can also cleave the P–F and P–O bonds found in organophosphorus
compounds, including the nerve agents, soman and sarin. The advantages of using hyperthermophilic enzymes in biodetoxification
strategies are based on their enzyme stability and efficiency. Therefore, it is advantageous to examine new thermostable prolidases
for potential use in biotechnological applications. Two thermostable prolidase homologs, PH1149 and PH0974, were identified
in the genome of Pyrococcus horikoshii based on their sequences having conserved metal binding and catalytic amino acid residues that are present in other known
prolidases, such as the previously characterized Pyrococcus furiosus prolidase. These P. horikoshii prolidases were expressed recombinantly in the Escherichia coli strain BL21 (λDE3), and both were shown to function as proline dipeptidases. Biochemical characterization of these prolidases
shows they have higher catalytic activities over a broader pH range, higher affinity for metal and are more stable compared
to P. furiosus prolidase. This study has important implications for the potential use of these enzymes in biotechnological applications
and provides further information on the functional traits of hyperthermophilic proteins, specifically metalloenzymes. 相似文献
20.
We have isolated a new extremely thermophilic fast-growing Geobacillus strain that can efficiently utilize xylose, glucose, mannose and galactose for cell growth. When grown aerobically at 72 °C, Geobacillus LC300 has a growth rate of 2.15 h−1 on glucose and 1.52 h−1 on xylose (doubling time less than 30 min). The corresponding specific glucose and xylose utilization rates are 5.55 g/g/h and 5.24 g/g/h, respectively. As such, Geobacillus LC300 grows 3-times faster than E. coli on glucose and xylose, and has a specific xylose utilization rate that is 3-times higher than the best metabolically engineered organism to date. To gain more insight into the metabolism of Geobacillus LC300 its genome was sequenced using PacBio׳s RS II single-molecule real-time (SMRT) sequencing platform and annotated using the RAST server. Based on the genome annotation and the measured biomass composition a core metabolic network model was constructed. To further demonstrate the biotechnological potential of this organism, Geobacillus LC300 was grown to high cell-densities in a fed-batch culture, where cells maintained a high xylose utilization rate under low dissolved oxygen concentrations. All of these characteristics make Geobacillus LC300 an attractive host for future metabolic engineering and biotechnology applications. 相似文献