Steroidogenic factor-1 expression is transiently repressed and c-myc expression and deoxyribonucleic acid synthesis are induced in rat granulosa cells during the periovulatory period

The expression of steroidogenic factor 1 (SF-1), cytochrome P450 aromatase (P450arom), and cytochrome P450 cholesterol side-chain cleavage (P450scc) was examined during the periovulatory period. Immature rats were injected with eCG to induce development of ovarian follicles to the preovulatory stage. At 48 h after the eCG injection, the LH surge was simulated by an injection of an ovulatory dose of hCG, and RNA was isolated at 0, 2, 4, 6, 8, and 24 h after hCG injection. The mRNA levels for SF-1, P450arom, and P450scc were relatively high in total ovarian RNA samples from eCG-treated rats. Levels of SF-1 and P450arom mRNA decreased within 2 h after injection of hCG. The SF-1 mRNA levels gradually increased from 4 to 24 h. Aromatase levels remained undetectable until 24 h after hCG. P450scc mRNA levels increased throughout the 24-h period after hCG. Levels of SF-1 and P450arom, but not P450scc, mRNA were also reduced in RNA samples from isolated granulosa cells at 4 h after hCG treatment relative to those from eCG-treated rats. In situ hybridization analysis also revealed that hCG uniformly suppressed SF-1 mRNA levels an all granulosa cells compared to those of eCG-treated controls. The relationship of SF-1 expression to immediate/early gene expression and cell cycle traverse was also examined. C-myc mRNA levels were induced by up to 10-fold at 4 h after hCG injection. Similarly, DNA synthesis, as measured by the percentage of granulosa cells that incorporated 5'-bromodeoxyuridine, was increased from 16 +/- 4% in eCG-treated rats to 61 +/- 7% at 4 h after hCG treatment (p < 0.05). This study provides the novel finding that SF-1 expression is transiently repressed to very low levels in response to the LH surge. Further, these studies suggest that granulosa cells traverse the cell cycle before becoming terminally differentiated luteal cells.

Role of cell-cell adhesion in the regulation of prolactin gene expression by extracellular CaCl(2)

We have investigated a role for calcium-dependent cell-cell adhesion in the regulation of prolactin gene expression in rat pituitary GH(3) cells. Cells cultured in a calcium-free, serum-free medium (SFM) express low levels of prolactin and growth hormone mRNA. As expected, addition of 0.5 mM CaCl(2) to GH(3) cells in SFM produced a specific, severalfold increase in prolactin mRNA levels. CaCl(2) also promoted intercellular adhesion, during which cells assembled end-to-end in to cords. Prolactin mRNA increased after a delay of several hours. This latency period ranged from 4-12 h among different experiments, but always occurred after the onset of cell-cell adhesion. The voltage-sensitive calcium channel (VSCC) blocker, nitrendipine, inhibited the CaCl(2)-induced increase in prolactin mRNA without affecting cord formation. However, the VSCC agonist, BAY K-8644, was unable to induce prolactin gene expression prior to the onset of intercellular adhesion at 8 h, even though it produced a cellular response (tyrosine phosphorylation of a ca. 130-kDa protein) within 30 min. Blocking cell-cell adhesion inhibited the calcium-dependent induction of prolactin gene expression. Low levels (0.0025-0.02%) of trypsin blocked cell-cell adhesion and the prolactin mRNA induction by CaCl(2) without affecting the levels of other mRNAs or cell-matrix adhesion. Heparin also specifically blocked the induction of both cell-cell adhesion and prolactin gene expression. Based on these data, we propose a role for both VSCCs and calcium-dependent cell-cell adhesion in the induction of prolactin gene expression by extracellular CaCl(2).

Complete nucleotide sequence of a cryptic plasmid, pBAW301, from the ruminal anaerobe Ruminococcus flavefaciens R13e2

The complete nucleotide sequence of a cryptic plasmid designated pBAW301, from the Gram-positive ruminal bacterium Ruminococcus flavefaciens R13e2, has been determined. This plasmid is 1768 bp in size and has an overall G+C content of 43.5%. Computer analysis of the sequence data revealed an open reading frame, ORF1 (256 amino acids), which is similar to the Rep protein of the Bacillus borstelensis plasmid pHT926. ORF1 is preceded by Shine-Dalgarno and Escherichia coli-10 and -35 like sequences. Nine smaller open reading frames showed no significant homologies to known protein sequences. Analysis of replication intermediates and the nucleotide sequence indicate that the plasmid does not replicate by a rolling-circle mode of replication similar to other plasmids from Gram-positive bacteria. Moreover, sequences typical of theta replication origins were not found in the nucleotide sequence of pBAW301. These data suggest that this plasmid either replicates by an as yet undescribed mechanism, or represents a new class of theta replicating plasmids.

Tumor necrosis factor beta gene polymorphism and early primary kidney allograft loss

The purpose of this study was to examine the association of TNFB alleles and genotypes in recipients experiencing early cadaveric kidney graft loss and non-early graft loss. Because the TNFB1 allele is associated with increased production of the TNF beta lymphotoxin following PHA mitogenic stimulation in vitro, the frequency of this allele was examined in renal transplant recipients experiencing early graft loss. A similar expression of TNFB alleles and genotypes was found in the early regraft loss group (< or = 3 months; n = 16) and non-early graft loss group (n = 81). We conclude that alleles of the TNFB gene are not risk factors for early cadaveric kidney graft loss.

Dental caries, restoration and tooth conditions in U.S. adults, 1988-1991. Selected findings from the Third National Health and Nutrition Examination Survey

This article provides estimates of dental caries experience and selected restorative and tooth conditions among U.S. adults, obtained from Phase 1 (1988-1991) of the Third National Health and Nutrition Examination Survey. Between 1988 and 1991, 94 percent of adults in the United States showed evidence of past or present coronal caries. Based on the data collected, the authors estimate that about 40.5 percent, or 61.6 million, dentate adults had at least one tooth or tooth space that could potentially benefit from professional treatment. Minimally, it is estimated that 135.6 million tooth or tooth spaces among U.S. adults may benefit from professional treatment. These estimates supplement information available from the DMF index to provide a broader profile of the impact of dental caries on permanent tooth of U.S. adults.

Steroidogenic factor-1 as a positive regulator of rat granulosa cell differentiation and a negative regulator of mitosis

Ovarian follicles contain small nonaromatase-expressing and large aromatase-expressing granulosa cells (GCs). The present studies were designed to determine whether small GCs can differentiate into large GCs and/or express aromatase. Additional studies were conducted to assess the role of steroidogenic factor-1 (SF-1), an orphan nuclear receptor, in regulating GC differentiation and proliferation. For these studies, small GCs were isolated from immature rats by Percoll gradient centrifugation and cultured for up to 48 h with FSH and/or 8-bromo-cAMP (8-br-cAMP). FSH/8-br-cAMP induced a 2-fold increase in SF-1 messenger RNA levels within 4 h. This increase was maintained throughout the culture period. By 24 h culture, FSH/8-br-cAMP increased the percentage of large GCs. It was not until 48 h of culture with FSH and 8-br-cAMP that aromatase expression increased. This increase was detected by both Western blot and quantitative immunocytochemistry. 8-br-cAMP alone did not promote GC differentiation. Small GCs were then cultured with FSH/8-br-cAMP in the presence or absence of an antisense oligonucleotide complementary to the putative SF-1 ligand-binding site (SF-1 AS). As a control, small GCs were cultured with FSH/8-br-cAMP and an 18-mer nonsense oligonucleotide (SF-1 NS). The SF-1 AS, but not the SF-1 NS, prevented FSH/8-br-cAMP from increasing 1) SF-1 messenger RNA levels, 2) transcription of a SF-1(x2) promoter/luciferase construct, 3) GC size, and 4) aromatase expression. In a third series of experiments, small GCs were cultured for 24 h in 1) control media supplemented with 2) a mitogen, phorbol ester [12-O-tetraphorbol acetate (TPA)], 3) FSH/8-br-cAMP, or 4) both. TPA increased the number of GCs by 51 +/- 9%. FSH/8-br-cAMP completely blocked TPA-induced mitosis. When small GCs were cultured with FSH/cAMP, TPA, and SF-1 AS, the number of GCs increased by 50 +/- 7%. This increase was not observed with SF-1 NS. Taken together, these data demonstrate that SF-1 is expressed in both small and large GCs, and enhanced SF-1 expression is part of the molecular mechanism associated with GC differentiation. Interestingly, SF-1 not only regulates differentiation, but also inhibits TPA-induced GC mitosis.

An endo-beta-1,4-glucanase gene (celA) from the rumen anaerobe Ruminococcus albus 8: cloning, sequencing, and transcriptional analysis

A genomic library of Ruminococcus albus 8 DNA was constructed in Escherichia coli using bacteriophage lambda ZapII. This library was screened for cellulase components and several Ostazin brilliant red/carboxymethyl cellulose positive clones were isolated. All of these clones contained a common 3.4-kb insert, which was recovered as a plasmid by helper phage excision. The carboxymethyl cellulase coding region was localized to a 1.4-kb region of DNA by nested deletions, and a clone containing the entire celA gene was sequenced. Analysis of the sequence revealed a 1231-bp open reading frame, coding for a protein of 411 amino acids with a predicted molecular weight of 45 747. This protein, designated CelA, showed extensive homology with family 5 endoglucanases by both primary amino acid sequence alignment and hydrophobic cluster analysis. Cell-free extracts of E. coli containing the celA clone demonstrated activity against carboxymethyl cellulose and acid swollen cellulose but not against any of the p-nitrophenol glycosides tested, indicating an endo-beta-1,4-glucanase type of activity. In vitro transcription-translation experiments showed that three proteins of 48,000, 44,000, and 23,000 molecular weight were produced by clones containing the celA gene. Northern analysis of RNA extracted from R. albus 8 grown on cellulose indicated a celA transcript of approximately 2700 bases, whereas when R. albus 8 was grown on cellobiose, celA transcripts of approximately 3000 and 600 bases were detected. Primer extension analysis of these RNAs revealed different transcription initiation sites for the celA gene when cells were grown with cellulose or cellobiose as the carbon source. These two sites differed by 370 bases in distance. A model, based on transcription and sequence data, is proposed for celA regulation.

Selected restoration and tooth conditions: United States, 1988-1991

The DMF index provides one source of information on past and present dental caries experience; however, important limitations hinder its ability to characterize fully the impact of dental caries. The purpose of this paper is to describe a measure of selected restoration and tooth conditions that supplements information from the DMF index and to report on the application of this measure as part of the Third National Health and Nutrition Examination Survey, Phase 1, conducted between 1988 and 1991. Data from this survey were used to estimate the prevalence and severity of selected disaggregated physical and biological oral conditions among dentate adults aged 18 to 74 years. Trained, standardized, and calibrated dentist examiners assessed 28 permanent teeth or tooth spaces for each of 6,767 subjects. Teeth or tooth spaces were classified based on criteria for: defective intracoronal restorations, crowns, or bridges; gross loss of tooth structure associated with a restoration; pulpal involvement; or retained roots. Approximately 40.5%, or 61.6 million, dentate adults had at least one tooth or tooth space that met the criteria. Among all persons, an average of 0.9 teeth or tooth spaces met the criteria for at least one category. Adults with at least one scored tooth or tooth space had an average of 2.2 such teeth or tooth spaces. Data from this assessment supplement information available from the DMF index to provide a broader profile of the impact of dental caries on permanent teeth of US adults.

DNA sequence and transcriptional characterization of a beta-glucanase gene (celB) from Ruminococcus flavefaciens FD-1

The recombinant clone pBAW101 (in pBluescript SK-) contains the celB endoglucanase gene from Ruminococcus flavefaciens FD-1. Subcloning indicated that the endoglucanase activity expressed was present within a 2.4-kb insert (pBAW104). The nucleotide sequence of the celB gene was determined, and upon analysis, revealed an open reading frame of 1943 nucleotides that encodes a polypeptide of 632 amino acids with a molecular weight of 69,414. A putative Shine-Dalgarno sequence was identified 6 bp upstream from the translation start site. The N-terminal 32 amino acid residues were typical of prokaryotic signal sequences. Hydrophobic cluster analysis (HCA) and DNA alignment of CelB to other published beta-glucanase polypeptide sequences in GenBank indicate that CelB belongs in HCA cellulase family 44. Primer extension analyses were performed using RNA isolated from R. flavefaciens grown on cellulose and cellobiose, and from Escherichia coli containing the plasmid clone pBAW104. Transcription is initiated at different sites in E. coli and R. flavefaciens. In the case of R. flavefaciens transcription is initiated at a C residue (nucleotides 329), 221 bp upstream from the translation start site. There were no regions resembling E. coli sigma 70-like promoter sequences present upstream from this putative transcription initiation site. In contrast, numerous transcription initiation sites were identified when RNA from E. coli was used in the primer extension analyses.

The costs and consequences of neglected medically necessary oral care

Oral diseases and conditions may adversely affect general health, and certain medical conditions may have a negative effect on oral health. However, little attention has been given to assessing the economic costs and consequences associated with care that is a direct result of, or has a direct impact on, an underlying medical condition and/or its resulting therapy. The costs can be significant for patients; their families; third-party payers such as insurance companies, Medicare, and Medicaid; and society. The health consequences of such conditions may dramatically affect function, morbidity, quality of life, and survival. This paper reviews one possible approach for identifying and measuring the costs and consequences associated with medically necessary oral health care and presents a framework for evaluating medically necessary oral health care. The paper also describes the cost components of care and the dimensions of health consequences. Finally, an example illustrates this approach. The summary information presented here is meant to offer concepts and ideas important in assessing the costs and health consequences associated with medically necessary oral health care. Individuals interested in a more detailed discussion of economic evaluation of health care programs and outcomes assessment are referred elsewhere. 10-23

Effect of weaning diet on the ecology of adherent lactobacilli in the gastrointestinal tract of the pig

Sixteen pigs were included in an investigation of the effects of weaning and weaning diet on the ecology of adherent Lactobacillus species in the gastrointestinal tract. At 28 d of age four pigs were killed and were designated as the preweaning control (PW). Four pigs remained on the sow (Sow), four pigs were fed a corn-soy-lactose (CSL) diet, and the remaining four pigs were fed a corn-soy (CS) diet. Pigs from the latter three treatments were killed at 38 d of age. Tissue samples were taken from the pars esophagus, ileum, and cecum and the adherent lactobacilli were enumerated using Rogosa SL agar. Bacterial colonies were randomly selected from Rogosa SL agar plates and speciated using cell type, morphology, and substrate fermentation tests. The species data were used to calculate the Shannon, Simpson, and evenness diversity indices. Shannon and Simpson diversity index values when averaged across tissues were lower (P < .05) for PW than for postweaning treatments (Sow, CSL, and CS) and lower (P < .05) when pigs receiving sow's milk (PW and Sow) were compared with pigs receiving the dry diets (CSL and CS). The diversity of adherent Lactobacillus is altered by the form of the diet fed to weanling pigs, and statistical ecological methods provide a powerful way of analyzing the ecology of the gastrointestinal tract.

Cellular and molecular mechanisms that mediate insulin-dependent rat granulosa cell mitosis

Rat ovarian follicles are composed of small and large granulosa cells (GC). The present studies demonstrate that small GCs undergo insulin- or phorbol ester-dependent mitosis in vitro. In order to examine the cellular and molecular events that account for insulin's mitogenic action, small GCs were cultured with either insulin, phorbol ester (TPA), or both insulin and TPA. Insulin and TPA increased GC numbers by 21 +/- 3% and 20 +/- 2% over control values, respectively (p < 0.05). Simultaneous addition of insulin and TPA increased GC numbers by 20 +/- 3% (p < 0.05). In a second experiment, small GCs were exposed to control medium, insulin, staurosporine (a protein kinase C [PKC] inhibitor), or both insulin and staurosporine. These studies revealed that insulin induced a 21 +/- 5% increase in GC numbers and that staurosporine blocked insulin's mitogenic action. These observations suggest that insulin mediates its mitogenic action through a PKC-dependent mechanism. Since the proto-oncogenes, c-fos and c-jun, are expressed during GC mitosis, studies were undertaken to determine whether or not the expression of these two proto-oncogenes products was enhanced by insulin. The expression of c-fos and c-jun proteins was assessed by immunocytochemistry. These studies showed that after 5 h, insulin increased the percentage of cells that stained for c-fos and c-jun by 15 +/- 2% and 19 +/- 4, respectively (p < 0.05). The expression of these proto-oncogenes was blocked by staurosporine. Both progesterone and 8-br-cAMP, which block insulin-dependent GC mitosis, also inhibited the expression of c-fos and c-jun.(ABSTRACT TRUNCATED AT 250 WORDS)

Nucleotide sequence and transcriptional analysis of the celD beta-glucanase gene from Ruminococcus flavefaciens FD-1

The nucleotide sequence of the celD gene, which encodes endoglucanase and xylanase activity, from Ruminococcus flavefaciens FD-1 was determined. The DNA sequence of celD contains an open reading frame of 1215 nucleotides that encodes a polypeptide of 405 amino acids with a molecular mass of 44,631 Da. The primary amino acid sequence of CelD was screened against the GenBank data base for similar polypeptide sequences and the analysis indicated that CelD has common features with endoglucanases from the family E cellulases. Both hydrophobic cluster and BESTFIT (Genetics Computer Group (University of Wisconsin) package) analyses confirmed this relationship. Pairwise alignments using BESTFIT revealed that CelD was most closely related to endE4 from Thermomonospora fusca over a 160 amino acid window. The histidine, aspartate, and glutamate residues identified as being essential for catalytic activity in family E cellulases are conserved in CelD. A Shine-Dalgarno-like sequence was present 5 base pairs (bp) upstream of the translation start site. Primer extension analysis indicated that different transcription initiation sites are used to initiate transcription of celD in Escherichia coli and R. flavefaciens. In the case of R. flavefaciens the transcription initiation site is at a T residue (nucleotide 273) 16 bp upstream from the translational start site. A region resembling a sigma 70-like-10 promoter sequence is present upstream from the transcription initiation site but there is no apparent-35 region. In contrast, transcription in E. coli is initiated at a C residue 258 bp upstream from the translational start site and a sequence resembling a omega 70-like-10 region is present 5 bp upstream of this residue.(ABSTRACT TRUNCATED AT 250 WORDS)

A quarter century of changes in oral health in the United States

This paper provides an overview of the oral health status of Americans since the 1960s. Data from seven national surveys, conducted between 1960 and 1987, have been presented. Estimates of coronal and root caries, periodontal diseases, and tooth loss were reviewed. In addition, data on edentulism and oral cavity and pharyngeal cancer were included. Although the purpose of this paper is descriptive rather than analytical, some important trends have been noted: The number of children who were free from dental caries increased dramatically between 1963 and 1987. By 1987, almost one-half of school children between the ages of 5 and 17 were caries-free. Among those children with dental decay, the number of teeth affected has also declined. The oral health of adults also improved during the 27-year period included in this review. In particular, the mean number of missing teeth and the percentage of edentulous adults have declined substantially. Trends in periodontal diseases were difficult to determine due to changes in the measures of periodontal diseases utilized in the surveys. In the most recent survey of employed U.S. adults, approximately 44 percent were found to have gingivitis and slightly more than 13 percent had periodontal pockets 4-5 mm in depth. Approximately 30,000 new cases of oral cavity and pharyngeal cancer were diagnosed in 1993, resulting in approximately 8,000 deaths. African Americans have higher incidence and mortality rates than white Americans and also have a much lower five-year survival rate.

Transcriptional analysis of the Clostridium cellulovorans endoglucanase gene, engB

An endoglucanase gene, which was shown to be identical to the previously sequenced engB gene [Attwood et al. (1993) Abstr. Ann. Meet. Am. Soc. Microbiol.], was isolated from a Clostridium cellulovorans genomic library. Because of the lack of transcriptional information concerning engB we examined its expression in C. cellulovorans and in the heterologous hosts Escherichia coli and C. acetobutylicum following transformation of engB. Northern analysis suggested that both E. coli and C. acetobutylicum produced several transcripts of various sizes. C. cellulovarans produced a single transcript of 1600 bp with the relative amount of engB mRNA from cellulose-grown cells being much greater than that from cellobiose-grown cells. Primer extensions showed that engB was transcribed from a single transcription initiation site in C. cellulovorans preceded by sequences similar to promoter sequences found in Gram-positive bacteria. Primer extensions from both E. coli and C. acetobutylicum strains containing the engB gene showed multiple transcription initiation sites, none of which corresponded to the site determined in C. cellulovorans. We conclude that transcriptional control of the engB gene is less stringent in heterologous backgrounds and postulate that expression of the engB gene in C. cellulovorans is increased in the presence of cellulose.

The use of 16S rRNA-targeted oligonucleotide probes to study competition between ruminal fibrolytic bacteria: pure-culture studies with cellulose and alkaline peroxide-treated wheat straw

Specific oligonucleotide probes targeted to sites on the 16S rRNA of Ruminococcus albus 8, Ruminococcus flavefaciens FD-1, and Fibrobacter succinogenes S85 and a domain Bacteria probe were used to study bacterial interactions during the fermentation of cellulose and alkaline hydrogen peroxide-treated wheat straw in monocultures, dicultures, and tricultures. Results showed that R. albus 8 inhibited the growth of R. flavefaciens FD-1 when grown as a diculture with cellulose or alkaline hydrogen peroxide-treated wheat straw as the carbon source. In dicultures containing R. albus 8 and F. succinogenes S85 grown on cellulose or alkaline hydrogen peroxide-treated wheat straw, competition was not detected. R. flavefaciens FD-1 outcompeted F. succinogenes S85 when cellulose was used as the carbon source. In tricultures with cellulose as the carbon source, R. flavefaciens FD-1 was inhibited, R. albus 8 appeared to dominate during the early phase of degradation (12 to 48 h), while F. succinogenes S85 became predominant during the later phase of degradation (60 to 70 h). When alkaline hydrogen peroxide-treated wheat straw was used as a growth substrate, F. succinogenes S85 showed better growth than either R. albus 8 or R. flavefaciens FD-1. However, R. flavefaciens FD-1 was present in small numbers throughout the incubation period, unlike the growth patterns when cellulose was the carbon source.

The use of 16S rRNA-targeted oligonucleotide probes to study competition between ruminal fibrolytic bacteria: development of probes for Ruminococcus species and evidence for bacteriocin production

A total of six oligonucleotide probes, complementary to the 16S rRNA, were evaluated for quantitative and determinative studies of Ruminococcus albus and Ruminococcus flavefaciens. On the basis of specificity studies, probes for R. albus (probe RAL196) and R. flavefaciens (probe RFL196) were selected to quantitate these species in mixed culture. In combination with a Fibrobacter succinogenes S85 subspecies probe (SUB1) and a domain Bacteria (formerly kingdom Eubacteria) probe (EUB338), they were used to quantitate these species competing in mixed cultures for cellobiose as the carbon source. In dicultures containing R. albus 8 and F. succinogenes S85, competition was not observed. However, R. flavefaciens FD-1 eventually outcompeted F. succinogenes S85 when cellobiose was the substrate. When R. albus 8 and R. flavefaciens FD-1 were grown together on cellobiose medium, R. albus 8 outcompeted R. flavefaciens FD-1, resulting in undetectable R. flavefaciens 16S rRNA only 1 to 3 h after inoculation, suggesting production of an antagonistic compound by R. albus 8 during rapid growth on soluble substrates. Further, when R. albus 8, R. flavefaciens FD-1, and F. succinogenes S85 were grown together in a triculture, R. flavefaciens FD-1 16S rRNA was detectable for only 2 h after inoculation, while R. albus 8 and F. succinogenes S85 showed a similar competition pattern to that of the dicultures. The results show that the Ruminococcus probes were effective in the measurement of relative populations of selected R. albus and R. flavefaciens strains during in vitro competition studies with F. succinogenes.(ABSTRACT TRUNCATED AT 250 WORDS)

The restriction endonuclease RflFII, isolated from Ruminococcus flavefaciens FD-1, recognizes the sequence 5'-AGTACT-3', and is inhibited by site-specific adenine methylation

Molecular studies of the rumen bacterium Ruminococcus flavefaciens are constrained by the lack of stable gene transfer systems. We report here on the characterization of RflFII, a restriction endonuclease isolated from R. flavefaciens FD-1. The enzyme is an isoschizomer of ScaI, and cleavage of the DNA is blunt-ended, between the internal TA dinucleotide sequence of 5'-AGTACT-3'. Chromosomal DNA preparations were used to demonstrate that adenine methylation of DNA within the sequence 5'-GTAC-3' inhibits both RflFII and the restriction endonucleases RsaI and ScaI. Chromosomal DNA from R. flavefaciens FD-1 is also host modified to protect against cleavage by ScaI.

Heterologous expression of endo-beta-1,4-D-glucanase from Clostridium cellulovorans in Clostridium acetobutylicum ATCC 824 following transformation of the engB gene

Heterologous expression of the Clostridium cellulovorans engB gene by Clostridium acetobutylicum BKW-1 was detected as zones of hydrolysis on carboxymethyl cellulose (CMC) Trypticase glucose yeast plates stained with Congo red. The extracellular cellulase preparation from C. acetobutylicum BKW-1 has a specific activity towards CMC which is more than fourfold that present in C. acetobutylicum ATCC 824. Western blot (immunoblot) analysis using the C. cellulovorans anti-EngB primary antibody demonstrated that an additional 44-kDa protein band was present in the supernatant derived from C. acetobutylicum BKW-1 but was not present in ATCC 824 or ATCC 824(pMTL500E).