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science lab manual cbse oxfordDownload full-text PDF Read full-text Download full-text PDF Read full-text Download citation Copy link Link copied Read full-text Download citation Copy link Link copied Citations (278) References (44) Figures (1) Abstract and Figures A total of 80 oral strains of Bacteroides gingivalis, B. asaccharolyticus, B. melaninogenicus subsp.Comparison of anaerobic and aerobic incubation with nine reference strains of these organisms showed no important differences. The key differential tests for black-pigmented Bacteroides strains and treponemes of oral origin were trypsin, alpha-glucosidase, and N-acetyl-beta-glucosaminidase. All Capnocytophaga strains produced distinctive aminopeptidase activities but varied in their glycosidic capabilities. The presence of a trypsin-like activity in B. gingivalis, T. denticola, and a group of Capnocytophaga strains may contribute to tissue destruction in periodontal disease.. Enzymatic activities of human oral spirochetes No.Comparison of anaerobic and aerobic incubation with nine reference strains of these organisms showed no important differences. The key differential tests for black-pigmented Bacteroides strains and treponemes of oral origin were trypsin, a-glucosidase, and N-acetyl-13- glucosaminidase. All Capnocytophaga strains produced distinctive aminopepti- dase activities but varied in their glycosidic capabilities. The presence of a trypsin-like activity in B. gingivalis, T. denticola, and a group of Capnocytophaga strains may contribute to tissue destruction in periodontal disease. The API ZYM system is a rapid test proce- dure which uses chromogenic substrates to de- tect 19 enzyme activities. It has been examined by several investigators for its applicability to the differentiation of streptococci (8, 32), actino- mycetes (10), peptococci (21), and gram-nega- tive anaerobes of clinical origin (6, 29).http://www.kovex.cz/_files/bronco-2-repair-manual-free.xml
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This report concerns the enzyme profile of three groups of organisms which may be involved in the etiology of periodontal disease. The black- pigmented Bacteroides species, especially Bac- teroides gingivalis (B. asaccharolyticus), have been recovered in elevated proportions from patients with advanced.The recently described genus, Capnocyto- phaga (12), has been reported to produce alveo- lar bone loss in monoinfected gnotobiotic rats (5, 9) and to cause human neutrophil (22) and fibro- blast (26) dysfunction in vitro. Oral spirochetes have long been observed to reach significantly high numbers in periodontitis lesions (15, 20) and to invade tissue in ulcerative gingivitis (14). Because of the importance of these organisms in periodontal disease, the API ZYM system was employed to survey the enzyme profiles to determine whether any potentially tissue-de- structive enzymes were present. As previously reported (B. E. Laughon, S. A. Syed, and W. J. Loesche, Abstr. Annu. Meet. Am. Soc. Micro- biol. 1980, C29, p. 279), we observed activities such as alkaline phosphatase, aminopeptidase, trypsin, and N-acetyl-13-glucosaminidase which were consistently present in certain species.MATERIALS AND METHODS Microorganism. A total of 89 strains consisting of 9 reference strains, 72 isolates from human periodontal plaque, 8 isolates from the dental plaque of beagle dogs, and 23 isolates of oral spirochetes were used in this study. The 89 strains included representatives of the genera Bacteroides, Capnocytophaga, and Trepo- nema. The following strains were obtained from the American Type Culture Collection: Bacteroides asac- charolyticus 25260, B. melaninogenicus subsp.In addition, A. Tanner of the Forsyth Dental Center, Boston, Mass., kindly provid- ed lyophilized cultures of Capnocytophaga ochracea strain 6, C. gingivalis strain 27, and C. sputigena strain 4. J0rgen Slots, State University of New York, Buffa- lo, generously provided the B.http://www.webantikvarium.eu/tmp/dell-printer-962-manual.xml gingivalis strain 2561 (ATCC 33277), and the FM and N9 spirochetes were obtained from R. M. Smibert, Virginia Polytechnic Institute, Anaerobe Laboratory, Blacksburg, Va. API ZYM system. API ZYM is a registered trade- mark of Analytab Products (Plainview, N.Y.) and Two reagents are used in the API ZYM system to develop the chromogenic substrates. Reagent A contains (per 100 ml): Tris, 25 g; HCl (37), 11 ml; and sodium dodecyl sulfate, 10 g. Reagent B contains 0.35 Fast Blue BB salt in 2- methoxyethanol. Test procedure. Stationary-growth phase bacteria other than spirochetes were removed from enriched Trypticase soy agar plates with an inoculating loop and suspended in 2 ml of sterile saline (0.85 NaCl) to a density approximating McFarland no. 5 or 6 turbidity standard. The spirochetes were harvested in the sta- tionary phase of growth by centrifugation for 1 min at 15,000 x g in an Eppendorf microcentrifuge (Brink- mann Instruments Inc., Westbury, N.Y.), washed once in sterile saline, and resuspended in saline as above. To develop the color reactions 1 drop each of reagents A and B was added to each microcupule. The color was allowed to develop for 5 to 15 min, and the intensities were recorded on a scale of 0 to 5 by comparison with the color chart provided by the manufacturer. RESULTS The API ZYM system produced consistent results in duplicate testings of representative strains (17 of the isolates examined). No im- portant qualitative differences were noted be- tween aerobic and anaerobic incubation condi- tions, except that B. gingivalis (ATCC 33277) produced a weak reaction in the anaerobic C-4 esterase assay and no reaction under aerobic conditions. In addition, this strain also showed a more intense acid phosphatase activity under anaerobic conditions. Because the atmosphere for incubation did not affect the majority of enzymes, all subsequent tests were performed aerobically.http://www.raumboerse-luzern.ch/mieten/how-uninstall-program-manually-xp The API ZYM activities elaborated by 80 oral isolates of black-pigmented Bacte- TABLE 1. Enzymatic activities of oral black-pigmented Bacteroides strains No.The remaining tests produced differentiating patterns among the genera exam- ined. The trypsin-like activity of B. gingivalis was very consistent and distinctive. None of the human strains of either B. melaninogenicus subsp.Moreover, the type strain of B. asaccharolyticus (ATCC 25260) failed to hydrolyze the trypsin substrate. The beagle dog isolates were variable for this charac- teristic. The black-pigmented Bacteroides spp. (Table 1) showed a range of glycosidic activities. Hu- man B. gingivalis strains were uniformly nega- tive for hydrolysis of glycosidic bonds, whereas a few canine black-pigmented Bacteroides strains were weakly positive for N-acetyl-p- glucosaminidase. All B. melaninogenicus subsp.All 19 strains of Capnocytophaga possessed strong leucine, valine, and cystine aminopepti- dase and a-glucosidase activities, but they ap- peared to segregate into three groups on the basis of four other enzymes (Table 2). Group I strains resembled the type strain of C. gingivalis in being negative for trypsin, negative or weakly positive for P-galactosidase, positive for,B-glu- cosidase, and negative for N-acetyl-3-glucosa- minidase. Group II strains included the C. och- racea and C. sputigena reference strains, 6 and 4, respectively. These were negative or weakly positive for trypsin and 3-glucosidase and posi- tive for,B-galactosidase and N-acetyl-3-glucosa- minidase. Group III consisted of seven strains which could not be associated with any de- scribed species. These organisms grew as spreading, rough-surfaced adherent colonies on -enriched Trypticase soy agar blood agar plates and usually caused pitting of the agar. Trypsin and chymotrypsin were positive,,-galacto- sidase was weak or negative, P-glucosidase was variable, and N-acetyl-p-glucosaminidase was negative. The two species of oral spirochetes examined, Treponema denticola and T. vincentii, both pro- duced moderate amounts of C-8 esterase, acid phosphatase, and phosphoamidase activities (Table 3). The T. denticola strains were consistently positive for trypsin and negative for N-acetyl-3- glucosaminidase, whereas the opposite was true for the T. vincentii strains. Very little hydrolytic activity was observed towards other glycosides. A summary of the key differential enzymes for oral species of Bacteroides and Treponema is shown in Table 4. The enzyme profile of the Capnocytophaga strains was not sufficiently re- TABLE 2. Enzymatic activities of human oral Capnocytophaga strains No.DISCUSSION The API ZYM system appears well-suited for the detection of enzymatic activity of the oral gram-negative bacteria examined in this study. The procedure is simple and convenient, does not require large cell masses, and may be per- formed under aerobic conditions. This system provides a rapid and reliable method for identifi- cation of the various black-pigmented Bacte- roides and Treponema species (Table 4). The Capnocytophaga strains can be identified to the genus, but not to the species, level. Human black-pigmented Bacteroides strains which did not hydrolyze glycosides but pos- sessed an amidase activity against N-benzoyl- DL-arginine-2-naphthylamide were invariably isolates of B. gingivalis. These organisms, previ- ously referred to as B. asaccharolyticus (4) differ from the type strain of B. asaccharolyticus in this trypsin-like activity toward N-benzoyl-DL- arginine-2-naphthylamide. Seven strains of B. asaccharolyticus isolated from nonoral sources were negative for the trypsin-like activity (29). These observations support the proposal of Coy- kendall et al. (4) for the recognition of a new species B. gingivalis and raise the possibility that this enzyme may contribute to the periodon- tal disease process. The lack of activity against the chymotrypsin substrate suggests a specificity similar to that of the mammalian trypsin. None of the B. melanin- ogenicus strains hydrolyzed the N-benzoyl-DL- arginine-2-naphthylamide substrate. The two subspecies examined produced glycosidase ac- tivities in the API ZYM system which correlate with their individual fermentative capabilities (7).Furthermore, the additional presence of trypsin and chymotrypsin activities in the rough-sur- faced strains suggests a broad phenotypic diver- sity within the proposed genus. The API ZYM system also detected N-acetyl-,3-glucosamini- dase activity in C. ochracea and C. sputigena, but not in C. gingivalis. This activity, observed with B. melaninogenicus subsp.The 23 strains of T. denticola and T. vincentii produced reactions in the API ZYM system which were consistent with the available infor- mation on their physiology (3, 24). T. denticola is known to be proteolytic for fibrin and gelatin (17, 24) but had not previously been reported to have trypsin and chymotrypsin activities. The two species could be differentiated on the basis of trypsin and N-acetyl-f3-glucosaminidase. The presence of a trypsin-like activity in B. gingivalis, T. denticola, and the unidentified group of Capnocytophaga strains deserves fur- ther comment. B. gingivalis and the spirochetes reach high proportions in plaques associated with advanced periodontitis but are rarely de- tected in health (15, 16, 23). This trypsin-like activity seems to be unique to these bacteria as more than 25 other oral species are known, with the exception of Bacterionema matruchotti and Rothia dentocariosa, to be trypsin negative (6, 10, 29, 31, unpublished data). The presence of this trypsin activity primarily in periodonto- pathic organisms suggests that this enzyme may be an important determinant of their virulence in periodontal disease. Such proteolytic activity may have a direct effect upon the junctional epithelium in the periodontal pocket as trypsin has been shown in vitro to disrupt cell-cell or cell-substratum adhesions (2, 30). In addition, trypsin seems to activate latent gingival tissue collagenase by destruction of a collagenase in- hibitor present in serum (1, 19). Finally, this bacterial enzyme could activate the alternate pathway of complement fixation causing the release of leukotactic factors C3a and C5a, as has been demonstrated with trypsin and certain bacterial proteinases (32). In fact, this trypsin- like enzyme could be the factor in periodontal plaques (11, 18) and pure cultures of T. denti- cola and B. gingivalis (13) which has been found to be chemotactic for polymorphonuclear leuko- cytes. These trypsin-like activities acting singly or in concert could effect significant pathology on the periodontium. The trypsin-like enzyme of these organisms should be further characterized to evaluate its relationship to pancreatic trypsin and its potential for periodontal pathogenesis. ACKNOWLEDGMENTS This work was supported by Public Health Service grant DE02731 and National Research Service award F32 DE05172 from the National Institute of Dental Research. We thank C. T. Hanks and Dennis F. Mangan for advice on the manuscript, Janice Stoll and Darlene Neil for technical assistance, and Connie Kato, Martha M. Jones, and Diana S. Stacy for copy preparation. American Society for Microbiolo- gy, Washington, D.C. 16. Loesche, W. J., S. A. Syed, E. M. Morrison, B. Laughon, and N. S. Grossman. 1981. The treatment of periodontal infections due to anaerobic bacteria with short term metronidazole.Red complex: Polymicrobial conglomerate in oral flora: A review Article Full-text available Nov 2019 JFMPC Rinkee Mohanty SwatiJoshi Asopa MDerick Joseph Uma Sharma Oral diseases are the complex host responses composed of a broad array of inflammatory cells, and cytokines, chemokines, and mediators derived from the cells resident in the gingival tissues, as well as from the emigrating inflammatory cells. A chronic polymicrobial challenge to the local host tissues triggers this response, which under certain circumstances, and in a subset of the population, leads to the progressing soft and hard tissue destruction that characterizes periodontitis. The red complex has been proposed as a pathogenic consortium, consisting of P. gingivalis, T. denticola, and T. forsythia. This review has attempted to examine the virulence potential and determinants of these commensal opportunists. View Show abstract. Further studies with individual Capnocytophaga species are essential to determine the exact role of Capnocytophaga in periodontal health and disease.. Detection and prevalence of Capnocytophaga in periodontal Health and disease Article Jan 2016 PushpaS Pudakalkatti AbhinavS Baheti SanjeeviniA Hattarki ReshmaM Naik View Biology of asaccharolytic black-pigmented Bacteroides species Article Mar 1988 Microbiol Rev D Mayrand S C Holt View Anaerobic Bacteriology Chapter Apr 2014 Stephen D. Allen Christopher L. Emery Jean A Siders View A Preliminary Study on the Ability of the Trypsin-Like Peptidase Activity Assay Kit to Detect Periodontitis Article Full-text available Sep 2020 Masanori Iwasaki Michihiko Usui Wataru Ariyoshi Tatsuji Nishihara This study aimed to explore whether the Trypsin-Like Peptidase Activity Assay Kit (TLP-AA-Kit), which measures the activity of N-benzoyl-dl-arginine peptidase (trypsin-like peptidase), can be used as a reliable tool for periodontitis detection in population-based surveillance. In total, 105 individuals underwent a full-mouth periodontal examination and provided tongue swabs as specimens for further analyses. The results of the TLP-AA-Kit were scored between 1 and 5; higher scores indicated higher trypsin concentrations. Severe and moderate periodontitis were identified in 4.8 and 16.2 of the study population, respectively. While further studies are necessary to validate our results, the results provided herein highlight the potential of the TLP-AA-Kit as a useful tool for the detection of periodontitis, particularly in severe cases, for population-based surveillance. View Show abstract Capnocytophaga spp.Indeed, DM-Periodontitis subjects manifest increased prevalence and severity of periodontitis than their non- DM-Periodontitis counterparts. The oral bacterial flora associated with DM-Periodontitis has not been thoroughly investigated. It is hypothesised that potentially elevated glucose levels in gingival crevicular fluid in DM-Periodontitis subjects could confer an ecological advantage for saccharolytic organisms such as Capnocytophaga spp. Members of this genus have been recovered from a range of periodontal diseases including DM-Periodontitis. In vitro studies have shown that Capnocytophaga spp.The main aim of this study was to investigate whether Capnocytophaga spp.Prior to commencement of the clinical study, fastidious anaerobe agar (FAA) was identified as the best culture medium for the recovery of these species from clinical samples. Identification of Capnocytophaga clinical isolates to species level was based on 16S rRNA PCR-RFLP with Cfo I as the restriction enzyme, developed specifically as part of this study. Total counts for Capnocytophaga spp.A total of 848 Capnocytophaga clinical isolates were isolated and identified using 16S rRNA PCR-RFLP. Statistical analyses were performed using multilevel modelling. A proportion (39) of Capnocytophaga clinical isolates were subjected to antimicrobial sensitivity testing. The majority were sensitive to most of the antibacterial agents used in clinical practice, with the exception of metronidazole. A micro-assay for the quantification of GCF- glucose was developed and used to quantify the GCF-glucose concentration in healthy, DM-Periodontitis and non-DM-Periodontitis subjects. The results showed that GCF-glucose concentration was higher in diseased and healthy sites in the DM- Periodontitis group. In conclusion, the results of this investigation have shown that Capnocytophaga spp.This could be due to the different subgingival ecological environment resulting from the elevated levels of GCF-glucose at these sites. View Show abstract Cloning and expression of a neutral phosphatase gene from Treponema denticola Article Apr 1995 INFECT IMMUN K Ishihara H K Kuramitsu We have isolated and characterized a neutral phosphatase gene, phoN, from Treponema denticola ATCC 35405. The gene was isolated from a T. denticola clone bank constructed in the medium-copy-number plasmid vector pMCL19. Subcloning and nucleotide sequencing of the DNA insert from one phosphatase clone, pTph14, revealed that the activity corresponded to an open reading frame consisting of 1,027 bp coding for a 37.9-kDa protein. Hydrophobicity analysis indicated that the protein exhibits some hydrophobic regions. Indeed, partial purification of the phosphatase suggested that the enzyme was membrane associated both in T. denticola and in the Escherichia coli clone. The pH optimum of the enzyme, approximately pH 6.4, indicated that it corresponded to a neutral phosphatase activity from T. denticola. An examination of possible natural substrates for the enzyme suggested that this enzyme hydrolyzes nucleoside di- and triphosphates. Northern (RNA) blot analysis revealed that this phosphatase gene is not likely to be present in an operon structure. View Show abstract Synergistic biofilm formation by Parvimonas micra and Fusobacterium nucleatum Article Sep 2019 ANAEROBE Akira Horiuchi Kokubu Eitoyo Takenobu Warita Kazuyuki Ishihara Parvimonas micra is frequently isolated from lesions of apical periodontitis and is a major disease-related pathogen. One of the main causes of apical periodontitis is extraradicular biofilm. In this study, we investigated polymicrobial biofilm formation by P. micra and species associated with apical periodontitis. The coaggregation activity of P. micra with partner strains was investigated by visual assays. Synergistic biofilm formation was evaluated by cocultures of P. micra and partner strains. Growth of planktonic cells was measured by evaluating the absorbance at OD660, and biofilm formation was examined by staining with crystal violet. The effects of soluble components on synergistic biofilm formation and planktonic cell growth were examined after coculture of P. micra and other strains separated with a 0.4-?m pore-size porous membrane. P. micra coaggregated with Fusobacterium nucleatum, Porphyromonas gingivalis, or Capnoctyophaga ochracea. P. micra showed no coaggregation with Staphylococcus aureus, S. epidermidis, or Prevotella intermedia. In mixed cultures, biofilm formation by P. micra and F. nucleatum was greater than that by P. micra and P. gingivalis or C. ochracea. In separated cocultures, planktonic cell growth of P. micra was enhanced by each of the three species. Biofilm formation by P. micra was enhanced by F. nucleatum or C. ochracea; however, no significant enhancement was observed with P. gingivalis. These data indicated that P. micra and F. nucleatum had synergistic effects in biofilm formation and that these effects may be important for colonization by these two species in apical periodontitis lesions. View Show abstract Microbiota Associated with Residual Clefts and Neighboring Teeth in Patients with Cleft Lip, Alveolus, and Palate Article Sep 1992 CLEFT PALATE-CRAN J Andrea Mombelli Urs Bragger Niklaus P. Lang Twenty patients with residual clefts or pronounced soft tissue grooves, treated for uni- or bilateral cleft lip, alveolus, and palate were included in this study. Ten patients were recalled for dental prophylaxis at regular intervals, 10 patients were not. One microbiologic sample was obtained from the cleft area and two samples from a tooth adjacent to the cleft (sites adjacent and distant to the cleft). Between the recall and the nonrecall group there were notable differences in the presence of anaerobic Gram-negative organisms. Fusobacterium spp., Prevotella melaninogenica, and P, intermedia were more often found in nonrecall patients. While rarely seen in recall patients, spirochetes and motile rods were a common feature of nonrecall patients. The putative periodontal pathogens Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were not detected in either group. The differences between the recall and the nonrecall groups were more pronounced when the respective samples from teeth were related to each other than when the samples obtained from the clefts were compared. The cleft flora was less complex irrespective of how good maintenance was and resembled the flora of teeth of well-maintained patients. Samples from clefts were never Wolinella positive, and harbored significantly less Capnocytophaga and Actinomyces viscosus than samples from dental sites. L'identification s'appuie souvent sur la determination de caracteres phenotypiques, comprenant l'etude des differents metabolismes, pouvant etre realisee a l'aide de systemes commercialises dont certains sont automatises. L'objet de notre etude a ete d'evaluer les performances de cette carte au laboratoire de Bacteriologiedu CHU de Nancy, vis-a-vis de 315 souches cliniques appartenant a des especes revendiquees par la base de donnees, et de 19 souches appartenant a des especes non revendiquees.Parmi les 315 souches cliniques, 98,7 ont ete d'emblee correctement identifiees au niveau du genre, et 88,5 au niveau de l'espece. Les souches appartenant aux Bacteroides du groupe fragilis, a l'espece B. ureolyticus, au genre Fusobacterium, aux cocci, aux bacilles a Gram positif non sporules et aux genres Corynebacterium et Arcanobacterium, ont ete bien identifiees. La rapidite d'un tel systeme pourrait cependant etre remise en cause par d'autres techniques emergentes, telles que la spectrometrie de masse permettant notamment l'identification fiable de micro-organismes en quelques minutes. View Show abstract Show more Rapid identification of Actinomycetaceae and related bacteria Article Full-text available Sep 1978 J CLIN MICROBIOL Mogens Kilian Identification of new isolates belonging to the family Actinomycetaceae requires extensive numbers of biochemical tests, supplemented with gas-liquid chromatography determination of fermentation end products and, often, analysis of cell wall composition. This paper describes the results of the testing of 162 strains of Actinomycetaceae and related taxa for 20 different enzymatic activities including phosphatases, esterases, aminopeptidases, and glycosidases. The results of all tests were read after 4 h of incubation. The results obtained in the study provide significant new information on the biochemical properties of these groups of bacteria. An identification scheme based upon 13 selected tests, which allow the identification of these groups of bacteria within 4 h, is proposed. In addition, four strains of catalase-positive B. melaninogenicus subsp. The nonoral strains had 51 to 52 mol guanine plus cytosine, the human oral strains had 46.5 to 48.5 mol guanine plus cytosine, and the monkey catalase-positive strains had 42 to 43 mol guanine plus cytosine in their deoxyribonucleic acids. Some strains which fit the species description of B. asaccharolyticus were not genetically related to the three groups. A new species, B. gingivalis sp. nov., which comprises those strains that resemble B. asaccharolyticus but have 46.5 to 48.5 mol guanine plus cytosine, is described. These strains can also be distinguished serologically and by their production of phenylacetic acid.View Show abstract Generation by Bacterial Proteinases of Leukotactic Factors from Human Serum, and Human C3 and C51 Article Apr 1973 J IMMUNOL P. A. Ward J. Chapitis M. C. Conroy Irwin H. Lepow Proteinases derived from Serratia marcescens and group A, ?-hemolytic Streptococcus are each able to generate, by cleavage, leukotactic fragments from human C3 and C5. In whole human serum, the Serratia enzyme produces a C3-related leukotactic factor, while the streptococcal proteinase produces a C5-related factor. The finding that proteinases derived from bacteria are able to generate complement-dependent leukotactic factors suggests that this may be one mechanism by which bacteria incite and maintain inflammatory reactions in tissues. View Show abstract Spirochaetales, A Review Article Jan 1973 CRIT REV MICROBIOL Robert M. Smibert R. C. Johnson View The modulation of cellular contractility and adhesion by trypsin and EGTA Article Feb 1980 EXP CELL RES Martin Britch Terence David Allen The relationship of cell to substrate and the organisation of the cellular contractile system has been studied using whole-cell mount transmission electron microscopy (TEM). Trypsinisation results in a breakdown of the ordered contractile system and both cell-cell and cell-substrate adhesion. Studies with the respiratory inhibitor 2,4 dinitrophenol (DNP) have shown that cellular rounding mediated by trypsinisation is energy independent. The response to EGTA is confluence modulated. Confluent monolayers are induced to contract and detach as sheets, a response related here to the overlapping of the peripheral cytoplasm. Subconfluent cells contract centripetally withdrawing organelles to the perinuclear region. Withdrawal of organelles is accompanied by a redistribution of the contractile system. Contraction results in a rounded cell anchored to the substrate by numerous retraction fibrils. The response to EGTA is energy dependent. We propose a mechanism for this response based on ultrastructural and biochemical characterisation of the actomyosin system. Macromolecular material from the surface of these cells was characterized by DEAE-cellulose chromatography and cetylpyridinium chloride precipitation while the associated morphology of cell detachment was studied by phase contrast and scanning electron microscopy. Release of surface glycosaminoglycans by testicular hyaluronidase did not cause cell rounding or detachment. EDTA did not release cell-surface components, but caused cell contraction and detachment morphologically similar to that caused by trypsin. Large amounts of cell-surface glycoproteins and glycosaminoglycans were released by trypsin. From these observations it is concluded that hyaluronic acid is not a principal adhesive agent in the attachment of cells to a substrate. It is suggested that both EDTA and trypsin may have their primary effect upon the cytoskeleton. View Show abstract Show more Advertisement Recommendations Discover more about: Bacteroides Project Working Group on new TB drugs Barbara E. Laughon View project Article Trypsin-like activity in subgingival plaque. A diagnostic marker for spirochetes and periodontal dis. Subgingival plaque samples were collected from single sites of known pocket depth, and after dispersal by vortexing, aliquots were incubated overnight with BANA and were counted microscopically.