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Speltz ML, Morton K, Goodell EW, Clarren SK. Psychological functioning of children with craniofacial anomalies and their mothers: follow-up from late infancy to school entry. Cleft Palate Craniofac J 1993; 30:482-9. [PMID: 8218312 DOI: 10.1597/1545-1569_1993_030_0482_pfocwc_2.3.co_2] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Twenty-three mothers and their 5- to 7-year-old children with craniofacial anomalies (CFA) who were assessed during the child's infancy were followed. Three types of CFA were included: cleft lip and palate (CLP), isolated cleft palate (CP), and sagittal synostosis. Measures of child status focused on behavior-problem frequency and self-concept. Mothers completed self-report measures of emotional well-being, marital satisfaction, and social support. Results indicated that (1) a sizable minority (18%) of the children with CFA had clinically significant behavior-problem scores shown in concordant reports by parent and teacher of behavior problems; (2) individual differences in child functioning within the CFA group were predicted by observational measures of earlier mother-infant interaction during play and teaching situations; (3) mothers of children with CLP reported less favorable social support than mothers of children with CP or sagittal synostosis.
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Affiliation(s)
- M L Speltz
- University of Washington School of Medicine, Seattle
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Goodell EW, Studdert-Kennedy M. Acoustic evidence for the development of gestural coordination in the speech of 2-year-olds: a longitudinal study. J Speech Hear Res 1993; 36:707-727. [PMID: 8377484 DOI: 10.1044/jshr.3604.707] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Studies of child phonology have often assumed that young children first master a repertoire of phonemes and then build their lexicon by forming combinations of these abstract, contrastive units. However, evidence from children's systematic errors suggests that children first build a repertoire of words as integral sequences of gestures and then gradually differentiate these sequences into their gestural and segmental components. Recently, experimental support for this position has been found in the acoustic records of the speech of 3-, 5-, and 7-year-old children, suggesting that even in older children some phonemes have not yet fully segregated as units of gestural organization and control. The present longitudinal study extends this work to younger children (22- and 32-month-olds). Results demonstrate clear differences in the duration and coordination of gestures between children and adults, and a clear shift toward the patterns of adult speakers during roughly the third year of life. Details of the child-adult differences and developmental changes vary from one aspect of an utterance to another.
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Keck W, van Leeuwen AM, Huber M, Goodell EW. Cloning and characterization of mepA, the structural gene of the penicillin-insensitive murein endopeptidase from Escherichia coli. Mol Microbiol 1990; 4:209-19. [PMID: 2187143 DOI: 10.1111/j.1365-2958.1990.tb00588.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The putative structural gene mepA of the penicillin-insensitive murein endopeptidase from Escherichia coli was cloned and sequenced. N-terminal sequence determination with the isolated endopeptidase protein showed that this enzyme is coded by the mepA gene and that it is synthesized initially with an N-terminal signal peptide. No significant sequence homology with the other (penicillin-sensitive) murein endopeptidase (dacB) or any other protein was found. The precise chromosomal mapping position of mepA relative to two other genes, aroC and fabB, was shown to be 50.4 min. E. coli strains carrying multicopy plasmids with the mepA gene produced 5-6-fold more endopeptidase and secreted it into the periplasm, where it appeared to function normally in vivo since the release of cell wall peptides into the medium increased in parallel. The transformed cells were, however, not unusually sensitive to penicillin and their murein had a normal degree of cross-bridges.
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Affiliation(s)
- W Keck
- Department of Biochemistry, University of Groningen, The Netherlands
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Abstract
During bacterial growth, cell wall peptides are released from the murein and reused for the synthesis of new cell wall material. Mutants defective in peptide transport were unable to reutilize cell wall peptides, demonstrating that these peptides are taken up intact into the cytoplasm prior to reincorporation into murein. Furthermore, cell wall peptide recycling was shown to play an important physiological role; peptide transport mutants which were unable to recycle these peptides showed growth defects under appropriate conditions. Using mutants specifically defective in each of the three peptide transport systems, we showed that the uptake of cell wall peptides was mediated solely by the oligopeptide permease (Opp) and that neither the dipeptide permease (Dpp) nor the tripeptide permease (Tpp) played a significant role in this process. Our data indicate that the periplasmic oligopeptide-binding protein has more than one substrate-binding site, each with different though overlapping specificities.
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Abstract
The tripeptide (L-Ala-D-Glu-meso-diaminopimelic acid [A2pm]), tetrapeptide (L-Ala-D-Glu-A2pm-D-Ala), and dipeptide (A2pm-D-Ala) which are shed by Escherichia coli from the murein sacculus were found to be reused by the cells to synthesize murein. The tripeptide was used directly, without degradation, to form UDP-N-acetylmuramyl-L-Ala-D-Glu-A2pm. The tetrapeptide lost its carboxy-terminal D-Ala, apparently in the periplasm, before being used. The dipeptide was degraded to D-Ala and A2pm before uptake.
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Abstract
Escherichia coli W7 cells were found to release three different muropeptides into the culture medium: tetrapeptide (L-Ala-D-Glu-meso-diaminopimelic acid-D-Ala), tripeptide (L-Ala-D-Glu-meso-diaminopimelic acid), and a previously undescribed dipeptide (meso-diaminopimelic acid-D-Ala). From the rate of release of these three peptides, it was calculated that 6 to 8% of the murein in the sacculus was lost per generation.
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Abstract
In Escherichia coli, peptide cross bridges in the murein undergo turnover after they are synthesized. Peptide cross bridges formed in the presence of [3H]diaminopimelic acid were found to lose 3H label from their donor peptides after the [3H]diaminopimelic acid was removed from the growth medium. There was a corresponding increase in the amount of 3H label in acceptor peptides so that the total amount of label in the peptide cross bridges remained constant. Our explanation of this observation is that the cross bridges are cleaved by the cell, and the original 3H-labeled donor peptides are incorporated into new cross bridges. Since these 3H-labeled peptides are now only tetrapeptides, they can only be used as acceptors when new cross bridges are formed.
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Abstract
The intermediates in the biosynthetic pathway of murein were examined in two strains of Escherichia coli to determine whether they synthesized oligomeric precursors in vivo. No oligomeric precursors could be detected; the only intermediates found were the previously described UDP-N-acetylmuramyl peptides, and the two lipid-linked compounds, N-acetylglucosamyl-N-acetylmuramyl-(pentapeptide)-pyrophosphoryl-undecaprenol and N-acetylmuramyl-(pentapeptide)-pyrophosphoryl-undecaprenol. It was concluded that lipid-linked monomers are directly incorporated into the murein sacculus in vivo and do not pass through an oligomeric stage.
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Goodell EW, Fazio M, Tomasz A. Effect of benzylpenicillin on the synthesis and structure of the cell envelope of Neisseria gonorrhoeae. Antimicrob Agents Chemother 1978; 13:514-26. [PMID: 122527 PMCID: PMC352274 DOI: 10.1128/aac.13.3.514] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The effect of benzylpenicillin on the synthesis and morphology of the cell envelope of Neisseria gonorrhoeae was examined. Penicillin immediately stopped murein synthesis; it also enhanced the rate of turnover of glucosamine, but not diaminopimelic acid, in the murein. In addition, penicillin greatly increased the shedding of lipid and lipopolysaccharide into the medium. In the electron microscope, protrusions of the cell membrane were evident, as well as apparent holes in the murein cell wall. All of these changes occurred while active synthesis was taking place, before the lysis of the cells. Lysis could be prevented by growing the cells at low pH and high concentrations of Mg2+; however, the effects of penicillin on murein synthesis and turnover and on the release of lipid were not affected.
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Goodell EW, Schwarz U. Enzymes synthesizing and hydrolyzing murein in Escherichia coli. Topographical distribution over the cell envelope. Eur J Biochem 1977; 81:205-10. [PMID: 338301 DOI: 10.1111/j.1432-1033.1977.tb11942.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Envelopes from regions of the cell which in vivo show very little, if any, murein synthesis were isolated using the minicell-producing strain P678-54. Envelopes from minicells, representing in fact cell ends, were able to synthesize murein and to carry out transpeptidation in vitro; also all four murein hydrolase activities tested, carboxypeptidase, endopeptidase, amidase and transglycosylase, were found to be present. The specific activities of the murein synthesizing and degrading enzymes in envelopes derived from cell poles and from actively growing cells were similar. The topological distribution of murein-synthesizing enzymes and of murein hydrolases over the cell envelope is discussed.
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Abstract
Growth of E. coli at pH 5 protected the bacteria against the lytic effect of beta lactam antibiotics typically observed when the cells are grown at pH 7 or 7.5, i.e., the pH values routinely used in laboratory experiments. In contrast, the typical effects of beta lactam antibiotics on cellular shape and elongation and cell division appeared to be similar in cultures grown under neutral and acid pH conditions. The pH-dependent antibiotic tolerance can also be demonstrated with pneumococci, staphylococci, streptococci, and Bacillus subtilis. We suggest that the mechanism of the pH-dependent antibiotic tolerance may involve either the production of a more stable plasma membrane or the suppression of the activity of a murein hydrolase(s) that catalyzes the antibiotic-induced lysis; at least a fraction of these enzyme molecules may be localized at the cell surface and be accessible to experimental manipulation.
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Abstract
The morphogenetic capacity of E. coli was studied by converting the rod-shaped cells into spheres and then determining whether these spheres could revert to rods. The morphogenesis of cells was followed by immobilizing them in a viscous Methocel-containing medium. Two different types of spheres were prepared: cells which retained a mechanically intact sacculus, and osmotically sensitive sphaeroplasts lacking a sacculus. The sphaeroplasts were not able to revert to rods although they were able to synthesize a new sacculus. In contrast, spheres which had retained an intact sacculus were able to reshape themselves into rods. The were also able to form new ends at (or near) the sites of the ends on the original rods.
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Goodell EW, Schwarz U, Teather RM. Cell envelope composition of Escherichia coli K12: a comparison of the cell poles and the lateral wall. Eur J Biochem 1974; 47:567-72. [PMID: 4154844 DOI: 10.1111/j.1432-1033.1974.tb03727.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Eriksson KE, Goodell EW. Pleiotropic mutants of the wood-rotting fungus Polyporus adustus lacking cellulase, mannanase, and xylanase. Can J Microbiol 1974; 20:371-8. [PMID: 4822055 DOI: 10.1139/m74-057] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
By screening for mutants which could not degrade cellulose, several cellulase-less mutants were isolated from the wood-rotting fungus Polyporus adustus. Most of the mutants lacked mannanase and xylanase as well. In wild type, the level of cellulase, mannanase, and xylanase was higher when the fungus was grown in a medium containing cellulose than in a medium lacking cellulose. It is proposed that in P. adustus, the induction of this group of enzymes is under the control of a single common regulator gene.
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Abstract
Control, by the spores, over the elongation and the branching of the sporangiophore is described. If the sporangium is removed from a sporangiophore, the sporangiophore stops growing within a few hours. 6-16h later a branch grows from the defunct growing zone. This branch forms a new sporangium and spores, and then starts to elongate again. The original growing zone can be "rescued" by replacing the sporangium with another sporangium or a sporangium-sized drop of spores. If the original growing zone is rescued, then it continues growing and the sporangiophore does not form a branch. It can only be rescued, however, within the first 60 min after the original sporangium is removed.
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Affiliation(s)
- E W Goodell
- Division of Biology, California Institute of Technology, Pasadena
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Abstract
The respiration of stage-I,-III, and-IV sporangiophores of Phycomyces was measured. The [Formula: see text] of stages-I and-IV is low compared to that of actively growing mycelium. The [Formula: see text] of stage-III sporangiophores is somewhat higher than that of stages-I and-IV. As stage-I sporangiophores elongate their respiration rate increases proportionately. The respiration rate of stage-IV sporangiophores does not change as they elongate. In stage-IV sporangiophores the growing zone and the columella together consume as much oxygen as the rest of the sporangiophore does. Changes in the sporangiophore's growth rate have no effect on its oxygen consumption.
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Affiliation(s)
- E W Goodell
- Division of Biology, California Institute of Technology, Pasadena
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Bergman K, Burke PV, Cerdá-Olmedo E, David CN, Delbrück M, Foster KW, Goodell EW, Heisenberg M, Meissner G, Zalokar M, Dennison DS, Shropshire W. Phycomyces. Bacteriol Rev 1969; 33:99-157. [PMID: 4889151 PMCID: PMC378314 DOI: 10.1128/br.33.1.99-157.1969] [Citation(s) in RCA: 171] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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