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Turner TF, Trexler JC, Harris JL, Haynes JL. Nested cladistic analysis indicates population fragmentation shapes genetic diversity in a freshwater mussel. Genetics 2000; 154:777-85. [PMID: 10655229 PMCID: PMC1460930 DOI: 10.1093/genetics/154.2.777] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Recently developed phylogeographic analyses that incorporate genealogical relationships of alleles offer the exciting prospect of disentangling historical from contemporary events. However, the relative advantages and shortfalls of this approach remain to be studied. We compared the nested cladistic method to the more traditional analysis of variance approach in a study of intraspecific genetic variation in the freshwater mussel, Lampsilis hydiana. We surveyed 257 specimens for nucleotide sequence level variation in a fragment of the mitochondrial 16S rRNA gene. When compared side by side, nested cladistic analysis and analysis of molecular variance (AMOVA) identified fragmentation of Arkansas river populations from remaining populations to the southwest. Nested cladistic analysis identified a second, more recent separation of Ouachita and Upper Saline river populations that was not detected by AMOVA. Differences among analytical methods probably arise from treatment of spatial hierarchical information: hierarchical groups emerge via a parsimony criterion in nested cladistic analysis but must be specified a priori in AMOVA. Both methods identified significant genetic structure among localities within hierarchical groups. Results from AMOVA suggested little gene flow among local populations with an island model. However, inferences about process that gave rise to patterns at this level were not possible in nested cladistic analysis, because an ancestral (interior) haplotype was not observed for a key one-step clade in the parsimony network. Our results suggest that, under some circumstances, nested cladistic analysis has lower power than more traditional analysis of variance to infer processes at the local population level.
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Abstract
Hypoxic injury accounts for approximately 20 to 40% of stillbirths in published autopsy series. Antepartum fetal testing modalities can discriminate between the fetus at risk for hypoxic injury and the normally oxygenated fetus. These modalities have resulted in a significant reduction in this category of stillbirths. The physiologic underpinning for the antepartum testing is reviewed with a brief discussion of the two major approaches to testing.
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Harris JL, Maguire D. Developing a protocol to prevent and treat pediatric central venous catheter occlusions. JOURNAL OF INTRAVENOUS NURSING : THE OFFICIAL PUBLICATION OF THE INTRAVENOUS NURSES SOCIETY 1999; 22:194-8. [PMID: 10476135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Catheter occlusions are a common occurrence in pediatric patients with central venous catheters. These occlusions are attributable to many factors, such as mechanical problems caused by catheter and patient size, clot formation caused by blood product administration and laboratory sampling, drug precipitation, and lipid residues. Because of the significant patient risk and cost involved in replacing occluded central venous catheters, a multidisciplinary team used a quality improvement approach to determine the effectiveness of urokinase in pediatric patients. Data from the project enabled development of a decision tree for urokinase use. Statistics from the pilot test revealed that 85% of the catheter occlusions were related to thrombotic events, and urokinase was effective in all cases. However, 15% of central line occlusions were related to medication precipitates and were not effectively cleared with urokinase. Given the evidence that urokinase is effective only on fibrin-related occlusions, the decision tree was modified to improve success with occlusions caused by medication precipitates.
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Harris JL. Urban African American adolescent parents: their perceptions of sex, love, intimacy, pregnancy, and parenting. ADOLESCENCE 1999; 33:833-44. [PMID: 9886011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
This study examined the perceptions of twenty-two urban African American adolescent mothers and six adolescent fathers (across seven grade levels and a general education equivalency program) regarding sex, love, intimacy, pregnancy, and parenting. Structured interviews and focus groups were used to gather data. Demographic and personal history information was also obtained. Inductive data analysis using constant comparison methods was employed to identify patterns and themes within and across gender groups.
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Harris JL, Peterson EP, Hudig D, Thornberry NA, Craik CS. Definition and redesign of the extended substrate specificity of granzyme B. J Biol Chem 1998; 273:27364-73. [PMID: 9765264 DOI: 10.1074/jbc.273.42.27364] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Granzyme B is a protease involved in the induction of rapid target cell death by cytotoxic lymphocytes. Definition of the substrate specificity of granzyme B allows for the identification of in vivo substrates in this process. By using the combinatorial methods of synthetic substrate libraries and substrate-phage display, an optimal substrate for granzyme B that spans over six subsites was determined to be Ile-Glu-Xaa-(Asp downward arrowXaa)-Gly, with cleavage of the Asp downward arrowXaa peptide bond. Granzyme B proteolysis was shown to be highly dependent on the length and sequence of the substrate, supporting the role of granzyme B as a regulatory protease. Arginine 192 was identified as a determinant of P3-Glu and P1-Asp substrate specificity. Mutagenesis of arginine 192 to glutamate reversed the preference for negatively charged amino acids at P3 to positively charged amino acids. The preferred substrate sequence matches the activation sites of caspase 3 and caspase 7 and thus is consistent with the role of granzyme B in activation of these proteases during apoptosis. The caspase substrate poly(ADP)-ribose polymerase is cleaved by granzyme B in a cell-free assay at two sites that resemble the granzyme B specificity determined by the combinatorial methods. Many caspase substrates contain granzyme B cleavage sites and are proposed as potential granzyme B targets, suggesting a redundant function with certain caspases.
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Harris JL, Rogers WA, Qualls CD. Written language comprehension in younger and older adults. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 1998; 41:603-617. [PMID: 9638925 DOI: 10.1044/jslhr.4103.603] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
This study examined the effects of text genre and repeated reading on written language comprehension in younger (M = 21 years) and older (M = 72 years) healthy adults (N = 54). Participants verified four text-based statements (i.e., explicit, implicit, contradictory, and elaborated) after reading expository, narrative, and procedural texts. Verification accuracy was comparable for both age groups; however, text genre, statement-type, and repeated reading produced significant effects. Expository passages, explicit and implicit statements, and repeated reading yielded superior results. Procedural passages and contradictory and elaborated statements yielded less accurate results. Statement-types invoked multiple levels of cognitive representation across text genres and age groups. Overall, reading time was significantly faster for younger adults, and reading times were significantly faster for both age groups during the repeated reading trial. Text genre also influenced reading time, with expository passages read faster than narrative and procedural passages. These findings suggest the appreciable influences of text genre and repeated reading on measures of text processing and comprehension in healthy adults, irrespective of age.
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Abstract
Protein engineering is the application of knowledge to design and alter protein function and structure. Although powerful methods, from specific to random, have been developed for the redesign of protein architecture, their successful application is dependent on the information known about the protein. This database of information is providing a foundation for establishing rules that govern enzyme-substrate interactions.
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Abstract
Prostate cancer is the most commonly diagnosed cancer in men. The radical prostatectomy is the treatment of choice for localized cancer; however, this surgery carries with it the potential complication of urinary incontinence postoperatively. The increasing number of radical prostatectomies each year will thus lead to a growing number of patients suffering from postprostatectomy urinary incontinence. According to the medical literature, the treatment of postprostatectomy incontinence is almost always limited to pharmacological or surgical therapy. Because of the failure of the standard treatment options, many men are left to live with their incontinence. The guidelines for the treatment of urinary incontinence recommend the use of behavioral methods as first-line treatment for stress and urge incontinence. The potential treatment of postprostatectomy incontinence with the use of behavioral methods has a promising future for the advanced practice nurse and for the men who are affected.
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Ewoldt GR, Smyth MJ, Darcy PK, Harris JL, Craik CS, Horowitz B, Woodard SL, Powers JC, Hudig D. P-4 and RNKP-7, new granzyme-like serine proteases expressed in activated rat lymphocytes. THE JOURNAL OF IMMUNOLOGY 1997. [DOI: 10.4049/jimmunol.158.10.4574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
Serine proteases (granzymes) in killer lymphocytes are required for lymphocyte cytotoxic granules to lyse target cells. Herein we report the development of a 3-step PCR cloning technique to amplify novel granzyme genes and two new rat granzymes are described. Degenerate oligonucleotide primers were designed based on sequence motifs selectively expressed in granzymes. These motifs flank "delta" regions that are unique for each granzyme. Total RNA of RNK-16 cells or activated splenocytes was amplified by reverse transcriptase-PCR to obtain cDNA fragments of several new granzymes. Gene-specific primers based on these delta regions were then used for 3'-RACE to obtain clones with the 3' gene ends. Reverse (antisense) delta-based or active site serine primers were used with a granzyme 5'-UTR primer to obtain clones extending to the 5' ends. Using this technique, two new cDNAs, RNKP-4 and RNKP-7, which encode granzymes of 248 and 241 amino acids, respectively, were cloned from activated lymphocytes. RNKP-4 is likely the rat equivalent of mouse granzyme C. RNKP-7 is most closely related to granzymes F and G. Modeling of the predicted proteins suggests large/polar P1 (Gln/Asn) specificity for RNKP-4 and large/hydrophobic P1 (e.g., Phe) specificity for RNKP-7. These specific protease activities were found in cytotoxic RNK-16 lymphocyte granules indicating that the two new genes may be translated and stored as active granzymes.
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Ewoldt GR, Smyth MJ, Darcy PK, Harris JL, Craik CS, Horowitz B, Woodard SL, Powers JC, Hudig D. P-4 and RNKP-7, new granzyme-like serine proteases expressed in activated rat lymphocytes. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1997; 158:4574-83. [PMID: 9144469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Serine proteases (granzymes) in killer lymphocytes are required for lymphocyte cytotoxic granules to lyse target cells. Herein we report the development of a 3-step PCR cloning technique to amplify novel granzyme genes and two new rat granzymes are described. Degenerate oligonucleotide primers were designed based on sequence motifs selectively expressed in granzymes. These motifs flank "delta" regions that are unique for each granzyme. Total RNA of RNK-16 cells or activated splenocytes was amplified by reverse transcriptase-PCR to obtain cDNA fragments of several new granzymes. Gene-specific primers based on these delta regions were then used for 3'-RACE to obtain clones with the 3' gene ends. Reverse (antisense) delta-based or active site serine primers were used with a granzyme 5'-UTR primer to obtain clones extending to the 5' ends. Using this technique, two new cDNAs, RNKP-4 and RNKP-7, which encode granzymes of 248 and 241 amino acids, respectively, were cloned from activated lymphocytes. RNKP-4 is likely the rat equivalent of mouse granzyme C. RNKP-7 is most closely related to granzymes F and G. Modeling of the predicted proteins suggests large/polar P1 (Gln/Asn) specificity for RNKP-4 and large/hydrophobic P1 (e.g., Phe) specificity for RNKP-7. These specific protease activities were found in cytotoxic RNK-16 lymphocyte granules indicating that the two new genes may be translated and stored as active granzymes.
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Chaudhry SI, Harris JL, Challacombe SJ. Dental erosion in a wine merchant: an occupational hazard? Br Dent J 1997; 182:226-8. [PMID: 9115841 DOI: 10.1038/sj.bdj.4809352] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This paper reports a case of dental erosion apparently caused by wine tasting. Dental erosion can cause extensive damage to the dentition, thereby creating a variety of complex restorative problems. Within the literature dental erosion has been attributed to many factors, but to date there are no documented cases specifically linking it with wine tasting. The dental professional is ideally placed to implement early preventive regimes which would make the occupation less damaging to the dentition.
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Harris JL. The Trading Cards Program--using high school role models for drug abuse prevention. Public Health Rep 1996; 111:547-8. [PMID: 8955705 PMCID: PMC1381907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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Harris JL, Salus D, Rerecich R, Larsen D. Distinguishing detection from identification in subliminal auditory perception: a review and critique of Merikle's study. THE JOURNAL OF GENERAL PSYCHOLOGY 1996; 123:41-50. [PMID: 8901209 DOI: 10.1080/00221309.1996.9921258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Assertions made by Merikle (1988) regarding audio subliminal messages were tested. Seventeen participants were presented subliminal messages embedded in a white-noise cover, and three signal-to-noise (S/N) detection ratios were examined. Participants were asked to guess message presence and message content, to determine subjective/objective thresholds. Results showed that participants were unable to identify target words presented in this audio subliminal stimulus format beyond chance levels.
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Valesco M, Harris JL, Barcelona L, Bulmer GS, Gugnani HC, McAleer R, Negroni R. Practical mycology for low budget laboratories. JOURNAL OF MEDICAL AND VETERINARY MYCOLOGY : BI-MONTHLY PUBLICATION OF THE INTERNATIONAL SOCIETY FOR HUMAN AND ANIMAL MYCOLOGY 1994; 32 Suppl 1:211-5. [PMID: 7722787 DOI: 10.1080/02681219480000841] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Harris JL, Davidson EC. Sociologic aspects of pregnancy. Curr Opin Obstet Gynecol 1992; 4:797-801. [PMID: 1450341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Increasingly, social factors are recognized as having a major impact on pregnancy, childbearing, and prenatal care. This review examines some of the more recent societal developments that have influenced health care for pregnant women. Although human gestation is a biologic phenomena, it exists with the social context of personal needs, family, and community of the pregnant women. This social fabric determines the perception, management, and outcome of that gestation. Significant influences to examine include pregnant women in the work force; malpractice concerns of health care providers; issues related to the cost of health care in pregnancy; the legal rights of the pregnant woman versus the legal rights of the fetus; pregnancy and occupational health; and the role of stress in pregnancy outcome.
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Harris JL, Mosley JL. Haptic asymmetries in persons with and without mental retardation. AMERICAN JOURNAL OF MENTAL RETARDATION : AJMR 1992; 97:71-85. [PMID: 1497866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Adults with mild mental retardation and equal-MA children and adults without mental retardation were required to (a) tactually examine single letters, two-letter words, bigrams, and Chinese characters with their right or left index finger and (b) indicate whether a visually presented stimulus was the tactually examined stimulus by saying "same" or "different." The left hand was significantly better for "same" responses and the right hand, for "different" responses, suggesting that hemispheric processing is dependent on information-processing requirements rather than type of stimulus. A left hand advantage for "same" Chinese characters by the children and adults without mental retardation was due to an increase in right hand latencies rather than a decrease in left hand latencies, again suggesting that different types of analyses are employed by the two cerebral hemispheres. Adults with mental retardation had the poorest accuracy and slowest latencies for correct "different" responses and significantly less differentiation of "same" and "different" responses (A') for all stimulus types. They identified "same" letters, words, and bigrams significantly faster than Chinese characters with their left hand and showed a trend toward the differential processing of bigrams ("same" latencies) as a function of hand.
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Harris JL. Diabetes mellitus in pregnancy. West J Med 1992; 156:647-8. [PMID: 1615657 PMCID: PMC1003354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The Council on Scientific Affairs of the California Medical Association presents the following inventory of items of progress in obstetrics and gynecology. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and important clinical significance. The items are presented in simple epitome, and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, researchers, or scholars to stay abreast of these items of progress in obstetrics and gynecology that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another. The items of progress listed below were selected by the Advisory Panel to the Section on Obstetrics and Gynecology of the California Medical Association, and the summaries were prepared under its direction.
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Abstract
1. Given the current economic climate, the number of homeless persons, and the nature of their needs, nurses must be prepared to facilitate movement of all homeless persons toward self-care. 2. Nurses can contribute to the self-care of homeless elderly men by recognizing and eliciting requisites, associated actions, and nursing interventions that reinforce meeting of needs. 3. Study results support Orem's proposition that universal self-care requisites are common to all individuals regardless of age, sex, developmental level, health state, or internal or external conditions. 4. A number of participant's statements used to formulate themes suggested a relationship to more than one category of universal self-care requisites, which suggests that the categories are not mutually exclusive.
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Piestrup MA, Boyers DG, Pincus CI, Harris JL, Maruyama XK, Bergstrom JC, Caplan HS, Silzer RM, Skopik DM. Quasimonochromatic x-ray source using photoabsorption-edge transition radiation. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 43:3653-3661. [PMID: 9905454 DOI: 10.1103/physreva.43.3653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Harris JL. Self-care actions of chronic schizophrenics associated with meeting solitude and social interaction requisites. Arch Psychiatr Nurs 1990; 4:298-307. [PMID: 2260888 DOI: 10.1016/0883-9417(90)90048-p] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Solitude becomes a way of life and social interaction a scarce commodity for many chronic schizophrenics who are in institutional settings. This article describes the self-care actions associated with meeting solitude and social interaction requisites as reported by 10 institutionalized chronic schizophrenics. Eighteen solitude self-care actions and 10 social interaction self-care actions emerged from the interview data. The solitude self-care actions clustered around two distinct categories: distancing and organizing. The social interaction self-care actions clustered around one category, managing situations. The implications of this study extend to anyone who is in the position of providing care and support to an individual diagnosed as a chronic schizophrenic. Additional research is suggested to increase the generalizability of the findings of this study and to isolate conditions related to Orem's (1985) sets of actions for maintenance of a balance between solitude and social interaction.
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Harris JL, Elmore D. Brief: Knowledge-The Basis for Nurses' Growth. J Contin Educ Nurs 1990; 21:182-5. [PMID: 2116466 DOI: 10.3928/0022-0124-19900701-12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Sigler L, Harris JL, Dixon DM, Flis AL, Salkin IF, Kemna M, Duncan RA. Microbiology and potential virulence of Sporothrix cyanescens, a fungus rarely isolated from blood and skin. J Clin Microbiol 1990; 28:1009-15. [PMID: 2351719 PMCID: PMC267855 DOI: 10.1128/jcm.28.5.1009-1015.1990] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Sporothrix cyanescens has been recovered from blood and a finger lesion at several medical centers in the United States. The morphology and physiology of these and three additional isolates were studied. S. cyanescens was distinguished from S. schenckii and S. fungorum by white to lavender colonial pigmentation and from S. schenckii also by the formation of secondary conidia. All isolates of S. cyanescens grew well at 37 degrees C, were cycloheximide susceptible, strongly urease positive, and benomyl resistant, failed to hydrolyze starch, and were inhibited by sodium chloride in vitro at a concentration of greater than or equal to 12%. Study of S. cyanescens in a murine model by using intravenous inoculation failed to demonstrate an invasive pathogenic potential. The validity of the transfer of S. cyanescens to the new genus Cerinosterus Moore is discussed.
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Karp F, Mihaliak CA, Harris JL, Croteau R. Monoterpene biosynthesis: specificity of the hydroxylations of (-)-limonene by enzyme preparations from peppermint (Mentha piperita), spearmint (Mentha spicata), and perilla (Perilla frutescens) leaves. Arch Biochem Biophys 1990; 276:219-26. [PMID: 2297225 DOI: 10.1016/0003-9861(90)90029-x] [Citation(s) in RCA: 126] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Microsomal preparations from the epidermal oil glands of Mentha piperita, Mentha spicata, and Perilla frutescens leaves catalyze the NADPH- and O2-dependent allylic hydroxylation of the monoterpene olefin (-)-limonene at C-3, C-6, and C-7, respectively, to produce the corresponding alcohols, (-)-trans-isopiperitenol, (-)-trans-carveol, and (-)-perillyl alcohol. These transformations are the key steps in the biosynthesis of oxygenated monoterpenes in the respective species, and the responsible enzyme systems meet most of the established criteria for cytochrome P450-dependent mixed function oxygenases. The reactions catalyzed are completely regiospecific and, while exhibiting only a modest degree of enantioselectivity, are highly specific for limonene as substrate. Of numerous monoterpene olefins tested, including several positional isomers of limonene, only the 8,9-dihydro analog served as an alternate substrate for ring (C-3 and C-6) hydroxylation, but not side chain (C-7) hydroxylation. In addition to the regiospecificity of the allylic hydroxylation, these enzymes are also readily distinguishable based on differential inhibition by substituted imidazoles.
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Karp F, Harris JL, Croteau R. Metabolism of monoterpenes: demonstration of the hydroxylation of (+)-sabinene to (+)-cis-sabinol by an enzyme preparation from sage (Salvia officinalis) leaves. Arch Biochem Biophys 1987; 256:179-93. [PMID: 3111374 DOI: 10.1016/0003-9861(87)90436-x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A microsomal preparation from the epidermis of Salvia officinalis leaves catalyzed the NADPH- and O2-dependent hydroxylation of the monoterpene olefin (+)-sabinene to (+)-cis-sabinol. The reaction catalyzed is a key step in the biosynthesis of C3-oxygenated thujane monoterpenes, and the hydroxylase is highly specific for (+)-sabinene as substrate. The hydroxylase from leaf homogenates was solubilized and characterized with regard to reaction conditions, inhibitors, and activators. Activity was partially inhibited by rabbit anti-rat cytochrome P-450 and by CO, and the latter inhibition was reversed by 450 nm light. A CO-difference spectrum and type I substrate binding spectrum were obtained. The hydroxylase meets most of the established criteria for a cytochrome P-450-dependent mixed function oxygenase and represents one of very few enzyme systems of this type to be isolated from leaves of a higher plant.
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