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Wilkie RP, Neal AR, Johnston CA, Voute N, Lancefield CS, Stell MD, Medda F, Makiyi EF, Turner EM, Stephen Ojo O, Slawin AMZ, Lebl T, Mullen P, Harrison DJ, Ireland CM, Westwood NJ. Total synthesis of dehaloperophoramidine using a highly diastereoselective Hosomi–Sakurai reaction. Chem Commun (Camb) 2016; 52:10747-50. [DOI: 10.1039/c6cc05747k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Synthesis involving diastereoselective Hosomi–Sakurai reaction to install the contiguous quaternary stereocentres.
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Blazer LL, Storaska AJ, Jutkiewicz EM, Turner EM, Calcagno M, Wade SM, Wang Q, Huang XP, Traynor JR, Husbands SM, Morari M, Neubig RR. Selectivity and anti-Parkinson's potential of thiadiazolidinone RGS4 inhibitors. ACS Chem Neurosci 2015; 6:911-9. [PMID: 25844489 DOI: 10.1021/acschemneuro.5b00063] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Many current therapies target G protein coupled receptors (GPCR), transporters, or ion channels. In addition to directly targeting these proteins, disrupting the protein-protein interactions that localize or regulate their function could enhance selectivity and provide unique pharmacologic actions. Regulators of G protein signaling (RGS) proteins, especially RGS4, play significant roles in epilepsy and Parkinson's disease. Thiadiazolidinone (TDZD) inhibitors of RGS4 are nanomolar potency blockers of the biochemical actions of RGS4 in vitro. Here, we demonstrate the substantial selectivity (8- to >5000-fold) of CCG-203769 for RGS4 over other RGS proteins. It is also 300-fold selective for RGS4 over GSK-3β, another target of this class of chemical scaffolds. It does not inhibit the cysteine protease papain at 100 μM. CCG-203769 enhances Gαq-dependent cellular Ca(2+) signaling in an RGS4-dependent manner. TDZD inhibitors also enhance Gαi-dependent δ-OR inhibition of cAMP production in SH-SY-5Y cells, which express endogenous receptors and RGS4. Importantly, CCG-203769 potentiates the known RGS4 mechanism of Gαi-dependent muscarinic bradycardia in vivo. Furthermore, it reverses raclopride-induced akinesia and bradykinesia in mice, a model of some aspects of the movement disorder in Parkinson's disease. A broad assessment of compound effects revealed minimal off-target effects at concentrations necessary for cellular RGS4 inhibition. These results expand our understanding of the mechanism and specificity of TDZD RGS inhibitors and support the potential for therapeutic targeting of RGS proteins in Parkinson's disease and other neural disorders.
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Kealey S, Turner EM, Husbands SM, Salinas CA, Jakobsen S, Tyacke RJ, Nutt DJ, Parker CA, Gee AD. Imaging imidazoline-I2 binding sites in porcine brain using 11C-BU99008. J Nucl Med 2012; 54:139-44. [PMID: 23223380 DOI: 10.2967/jnumed.112.108258] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Changes in the density of imidazoline-I(2) binding sites have been observed in a range of neurologic disorders including Alzheimer's disease, Huntington's chorea, and glial tumor; however, the precise function of these sites remains unclear. A PET probe for I(2) binding sites would further our understanding of the target and may find application as a biomarker for early disease diagnosis. Compound BU99008 has previously been identified as a promising I(2) ligand from autoradiography studies, displaying high affinity and good selectivity toward the target. In this study, BU99008 was radiolabeled with (11)C in order to image the I(2) binding sites in vivo using PET. METHODS (11)C-BU99008 was radiolabeled by N-alkylation of the desmethyl precursor using (11)C-methyl iodide. A series of PET experiments was performed to investigate the binding of (11)C-BU99008 in porcine brains, in the presence or absence of a nonradiolabeled, competing I(2) ligand, BU224. RESULTS (11)C-BU99008 was obtained in good yield and specific activity. In vivo, (11)C-BU99008 displayed good brain penetration and gave a heterogeneous distribution with high uptake in the thalamus and low uptake in the cortex and cerebellum. (11)C-BU99008 brain kinetics were well described by the 1-tissue-compartment model, which was used to provide estimates for the total volume of distribution (V(T)) across brain regions of interest. Baseline V(T) values were ranked in the following order: thalamus > striatum > hippocampus > frontal cortex ≥ cerebellum, consistent with the known distribution and concentration of I(2) binding sites. Administration of a selective I(2) binding site ligand, BU224, reduced the V(T) to near-homogeneous levels in all brain regions. CONCLUSION (11)C-BU99008 appears to be a suitable PET radioligand for imaging the I(2) binding sites in vivo.
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Tyacke RJ, Fisher A, Robinson ESJ, Grundt P, Turner EM, Husbands SM, Hudson AL, Parker CA, Nutt DJ. Evaluation and initial in vitro and ex vivo characterization of the potential positron emission tomography ligand, BU99008 (2-(4,5-dihydro-1H-imidazol-2-yl)-1- methyl-1H-indole), for the imidazoline₂ binding site. Synapse 2012; 66:542-51. [PMID: 22290740 DOI: 10.1002/syn.21541] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2011] [Revised: 01/12/2012] [Accepted: 01/23/2012] [Indexed: 11/06/2022]
Abstract
The density of the Imidazoline₂ binding site (I₂BS) has been shown to change in psychiatric conditions such as depression and addiction, along with neurodegenerative disorders such as Alzheimer's disease and Huntington's chorea. The presence of I₂BS on glial cells and the possibility that they may in some way regulate glial fibrillary acidic protein has led to increased interest into the role of I₂BS and I₂BS ligands in conditions characterized by marked gliosis. In addition, it has been suggested that I₂BS may be a marker for human glioblastomas. Therefore, the development of a positron emission tomography (PET) radioligand for the I₂BS would be of major benefit in our understanding of these conditions. We now report the successful synthesis and initial pharmacological evaluation of potential PET radioligands for the I₂BS as well as the tritiation and characterization of the most favorable of the series, BU99008 (6), both in vitro and ex vivo in rat. The series as a whole demonstrated excellent affinity and selectivity for the I₂BS, with BU99008 (6) selected as the lead candidate to be taken forward for in vivo assessment. BU99008 (6) showed very good affinity for the I₂BS (K(i) of 1.4 nM; K(d) = 1.3 nM), good selectivity compared with the α₂ -adrenoceptor (909-fold). In addition, following peripheral administration, [³H]BU99008 demonstrated a heterogenous uptake into the rat brain consistent with the known distribution of the I₂BS in vivo. This, and the amenability of BU99008 (6) to radiolabeling with a positron-emitting radioisotope, indicates its potential as a PET radioligand for imaging the I₂BS in vivo.
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Turner EM, Blazer LL, Neubig RR, Husbands SM. Small Molecule Inhibitors of Regulator of G Protein Signalling (RGS) Proteins. ACS Med Chem Lett 2012; 3:146-150. [PMID: 22368763 DOI: 10.1021/ml200263y] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Recently regulators of G protein signalling (RGS) proteins have emerged as potential therapeutic targets since they provide an alternative method of modulating the activity of GPCRs, the target of so many drugs. Inhibitors of RGS proteins must block a protein-protein interaction (RGS-Gα), but also be cell and, depending on the therapeutic target, blood brain barrier permeable. A lead compound (1a) was identified as an inhibitor of RGS4 in a screening assay and this has now been optimised for activity, selectivity and solubility. The newly developed ligands (11b, 13) display substantial selectivity over the closely related RGS8 protein, lack the off-target calcium mobilisation activity of the lead 1a and have excellent aqueous solubility. They are currently being evaluated in vivo in rodent models of depression.
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Kellogg DS, Turner EM, Callaway C, Lee L, Martin JE. Particulate Fractions of Neisseria gonorrhoeae. Infect Immun 2010; 3:624-32. [PMID: 16558027 PMCID: PMC416206 DOI: 10.1128/iai.3.4.624-632.1971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Passage of gonococcal cells through a Ribi cell fractionator produced a mixture of protoplasm and cell particulates, the latter being separable in sucrose solutions. Separation of these particulates resulted in the detection of objects identified as cell walls and "plasts." The latter objects had an average diameter of 1.00 +/- 0.05 mum and consisted of spatially oriented granules surrounded by a membrane-like structure only. Cell wall structures were not observed with these plasts. Plasts were morphologically stable in distilled water and at low pH values. Although 50% more pressure was required to rupture plasts than whole cells, plast morphology was destroyed by organic solvents. Whole cell and plast morphology was examined by electron and phase microscopy, and certain correlations were made between structure and morphological stability. Cell wall antiserum reactivities were quantitatively different for plasts and cell walls. Serological reactivities of plasts were separable by sonic oscillation and differential centrifugation of the sonically treated material.
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Feldman AL, Alexander HR, Hewitt SM, Lorang D, Thiruvathukal CE, Turner EM, Libutti SK. Effect of retroviral endostatin gene transfer on subcutaneous and intraperitoneal growth of murine tumors. J Natl Cancer Inst 2001; 93:1014-20. [PMID: 11438567 DOI: 10.1093/jnci/93.13.1014] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Inhibiting tumor angiogenesis is a promising new strategy for treating cancer. Difficulties with the stability, manufacture, and long-term administration of recombinant antiangiogenic proteins have prompted investigators to use gene therapy to generate these proteins in vivo. We investigated whether transfer of the gene encoding the angiogenesis inhibitor endostatin into the murine liver cell line NMuLi could inhibit tumor growth in vivo. METHODS NMuLi cells were transduced with retroviral vectors containing the murine endostatin gene. The presence and function of endostatin in transduced cell supernatants were confirmed by competitive enzyme immunoassay and endothelial cell proliferation assays. Nude mice were given a subcutaneous or intraperitoneal injection with NMuLi cells, control transduced cells (NEF-null), or endostatin-transduced clones (NEF-Endo1 to 4) and were monitored for tumor growth. All statistical tests were two-sided. RESULTS Supernatants from the clone secreting the lowest amount of endostatin (NEF-Endo4, 28 ng/mL) inhibited endothelial cell proliferation by 6% (95% confidence interval [CI] = 0% to 12%), and those from the clone secreting the highest amount (NEF-Endo1, 223 ng/mL) inhibited endothelial cell proliferation by 20% (95% CI = 13% to 27%). Increased levels of endostatin were detected in tumor lysates, but not serum, of mice given a subcutaneous injection of NEF-Endo1 cells. After 63 days, mice given a subcutaneous injection of parental NMuLi or NEF-null cells had tumor volumes of 2400 mm(3) (95% CI = 1478 mm(3) to 3300 mm(3)) and 2700 mm(3) (95% CI = 2241 mm(3) to 3144 mm(3)), respectively, compared with mean tumor volumes of less than 30 mm(3) in mice given an injection of NEF-Endo clones, a statistically significant difference (P<.001). After 123 days, all 16 mice given an intraperitoneal injection of parental NMuLi or NEF-null cells had died, compared with only three (9%) of 32 mice given an injection of NEF-Endo clones. CONCLUSIONS Retroviral endostatin gene transfer leads to secretion of functional endostatin that is sufficiently active to inhibit tumor growth. Further studies of retroviral endostatin gene transfer for the treatment of cancer are warranted.
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Lans TE, Bartlett DL, Libutti SK, Gnant MF, Liewehr DJ, Venzon DJ, Turner EM, Alexander HR. Role of tumor necrosis factor on toxicity and cytokine production after isolated hepatic perfusion. Clin Cancer Res 2001; 7:784-90. [PMID: 11309322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
PURPOSE Isolated limb or liver perfusion with tumor necrosis factor (TNF) and melphalan results in regression of advanced cancers in the majority of treated patients. However, the contribution of TNF to the efficacy of isolation perfusion with melphalan has not been demonstrated conclusively in random assignment trials. Furthermore, TNF is an inflammatory cytokine and may be associated with significant systemic and regional toxicity. This study was conducted to characterize the toxicity and secondary cytokine production attributable to TNF by comparing these parameters in patients undergoing isolated hepatic perfusion (IHP) using melphalan with or without TNF. EXPERIMENTAL DESIGN Thirty-two patients with unresectable colorectal cancer confined to the liver underwent a 60-min hyperthermic IHP using 1.5 mg/kg melphalan alone (n = 17) or with 1.0 mg of TNF (n = 15) with inflow via the gastroduodenal artery and outflow via an isolated segment of inferior vena cava. Complete vascular isolation was confirmed using the I-131 radiolabeled albumin-monitoring technique. Post-IHP parameters of hepatic and systemic toxicity and cytokine levels [TNF, interleukin (IL)-6 and IL-8] in perfusate and serum were measured. RESULTS Levels of IL-6 and IL-8 in perfusate at the end of the 60-min IHP were significantly higher in TNF-treated patients (P < or = 0.001). Peak systemic IL-6 and IL-8 levels post-IHP were also significantly higher in TNF-treated compared with non-TNF-treated patients (P < 0.0001) by 28- and 268-fold, respectively. The peak levels of these cytokines were associated with significantly lower systolic blood pressure and higher heart rate and mean pulmonary artery blood pressure in TNF-treated patients during the first 48 h post-IHP (P < or = 0.03). Serum bilirubin levels were significantly higher (P = 0.017) and platelets lower (P = 0.03) in TNF-treated compared with non-TNF-treated patients. However, elevations in aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase were not significantly different between groups and returned toward baseline within 1 week after IHP. CONCLUSIONS Addition of TNF to melphalan during IHP results in significant differences in post-IHP production of IL-6 and IL-8 with associated changes in mean arterial blood pressure and greater regional toxicity, as reflected in higher levels of serum bilirubin. However, these measurable differences were transient and did not appear to be of major clinical consequence. Prior to its routine use, the benefit of TNF in isolation perfusion should be demonstrated in random assignment trials.
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Feldman AL, Tamarkin L, Paciotti GF, Simpson BW, Linehan WM, Yang JC, Fogler WE, Turner EM, Alexander HR, Libutti SK. Serum endostatin levels are elevated and correlate with serum vascular endothelial growth factor levels in patients with stage IV clear cell renal cancer. Clin Cancer Res 2000; 6:4628-34. [PMID: 11156212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Clear cell renal carcinoma (CCRC) is a highly angiogenic tumor known to secrete vascular endothelial cell growth factor (VEGF). Endostatin is an endogenous antiangiogenic agent with antitumor activity in mice. The purpose of this study was to evaluate serum levels of endostatin in normal subjects and in patients with CCRC and to examine the relationship of these levels to circulating VEGF levels. Fifteen patients (mean age, 48 years) on a clinical protocol for stage IV CCRC at the National Cancer Institute were included in the study. Archived prenephrectomy serum samples were analyzed for endostatin and VEGF concentrations. Endostatin and VEGF levels were compared with those of an age-matched group of volunteer blood donors (n = 18) using a competitive enzyme immunoassay. Data were analyzed using the Mann-Whitney U test and the Spearman rank correlation. Median serum endostatin levels were 24.6 ng/ml (range, 15.1-54.0 ng/ml) in CCRC patients versus 14.1 ng/ml (range, 1.0-19.3 ng/ml) in healthy controls (P < 0.0001). Median VEGF levels were 3.4 ng/ml (range, 0.1-11.2 ng/ml) and 2.5 ng/ml (range, 0.1-4.2 ng/ml), respectively (P = 0.065). A highly significant correlation was observed between endostatin and VEGF levels among the CCRC patients (r = 0.81, P = 0.0003) but not among controls (r = -0.22, P = 0.37). Endostatin levels are detectable in serum from healthy subjects as well as from CCRC patients. Levels are significantly elevated and correlate with VEGF levels in CCRC patients. Elucidating the nature of this correlation may lend insight into the regulation of tumor angiogenesis in patients with renal cancer.
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Gnant MF, Turner EM, Alexander HR. Effects of hyperthermia and tumour necrosis factor on inflammatory cytokine secretion and procoagulant activity in endothelial cells. Cytokine 2000; 12:339-47. [PMID: 10805214 DOI: 10.1006/cyto.1999.0568] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The application of hyperthermia (HT) and tumour necrosis factor alpha (TNF) in isolation perfusion of the limb or liver results in regression of advanced cancers confined to these regions of the body in most patients and are thought to exert anti-tumour effects primarily on tumour neovasculature. However, the individual contribution of either treatment factor on endothelial cells (EC) are not known. In this study, we investigated the in vitro effects of moderate and severe HT on human umbilical vein EC (HUVEC) with and without TNF in clinically relevant doses. HUVEC were exposed to normothermia (37 degrees C) or moderate (39 degrees C) and severe (41 degrees C) HT for 90 or 180 min with or without TNF (1 microg/ml). Cell viability, cytokine secretion (IL-6, IL-8, VEGF, ICAM-1, VCAM-1, RANTES, E-selectin, P-selectin, L-selectin, and PECAM-1), and induction of procoagulant activity as reflected in tissue factor (TF) production were assessed at the end of the treatment period and at several time points thereafter. Neither HT nor TNF exerted significant cytotoxic effects on EC at the doses and temperatures used. HT resulted in increased production of PECAM-1 with little or no additional effect when combined with TNF. TNF caused increased secretion of IL-6, IL-8, ICAM-1, and VCAM-1 with little or no additional effect from HT. Increased E-selectin and RANTES levels were observed with TNF and HT only at 24 h after treatment. HT and TNF had mainly antagonistic effects on VEGF secretion with HT causing primarily decreased production and TNF causing increased VEGF secretion under all temperatures. Most notably, there was a rapid, prolonged and synergistic peak increase in procoagulant activity when TNF and HT were used in combination compared to TNF or HT treatment alone. These results indicate that TNF and HT exert primarily independent effects on inflammatory cytokine production in EC but synergistically increase procoagulant activity as reflected in TF production. These data provide a possible mechanism for the thrombotic effects in tumour neovasculature seen following isolation perfusion with these agents and provide a rationale for their combined use in this treatment setting.
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Sarraf P, Frederich RC, Turner EM, Ma G, Jaskowiak NT, Rivet DJ, Flier JS, Lowell BB, Fraker DL, Alexander HR. Multiple cytokines and acute inflammation raise mouse leptin levels: potential role in inflammatory anorexia. J Exp Med 1997; 185:171-5. [PMID: 8996253 PMCID: PMC2196098 DOI: 10.1084/jem.185.1.171] [Citation(s) in RCA: 585] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/1996] [Revised: 10/22/1996] [Indexed: 02/03/2023] Open
Abstract
Several inflammatory cytokines, most notably tumor necrosis factor (TNF) and IL-1, induce anorexia and loss of lean body mass, common manifestations of acute and chronic inflammatory conditions. In C57BL/6 female mice, the administration of TNF, IL-1, and, to a lesser extent, leukemia inhibitory factor (LIF), produced a prompt and dose-dependent increase in serum leptin levels and leptin mRNA expression in fat. IL-10, IL-4, ciliary neurotrophic factor, and IL-2, cytokines not known to induce anorexia or decrease food intake, had no effect on leptin gene expression or serum leptin levels. After administration of Escherichia coli lipopolysaccharide (LPS), leptin gene expression and leptin levels were increased. These findings suggest that leptin levels may be one mechanism by which anorexia is induced during acute inflammatory conditions.
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Norcliffe D, Turner EM. Comparison of five commercial kits for the determination of glycosylated haemoglobin. J Clin Pathol 1984; 37:1177-81. [PMID: 6490954 PMCID: PMC498962 DOI: 10.1136/jcp.37.10.1177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Five commercial chromatography kits for the measurement of glycosylated haemoglobin have been compared using blood specimens obtained from diabetic patients and from non-diabetic controls. Assessment was based on accuracy, general impressions of practicality, and overall performance. The precision of each technique was assessed by selecting five diabetic and five non-diabetic specimens and testing each one by each technique. All systems tested were of a high standard and the advantages and disadvantages of each system are discussed.
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Green DW, Aschaffenburg R, Camerman A, Coppola JC, Dunnill P, Simmons RM, Komorowski ES, Sawyer L, Turner EM, Woods KF. Structure of bovine beta-lactoglobulin at 6A resolution. J Mol Biol 1979; 131:375-97. [PMID: 40037 DOI: 10.1016/0022-2836(79)90082-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Turner EM, Wright M, Ward T, Osborne DJ, Self R. Production of ethylene and other volatiles and changes in cellulase and laccase activities during the life cycle of the cultivated mushroom, Agaricus bisporus. JOURNAL OF GENERAL MICROBIOLOGY 1975; 91:167-76. [PMID: 811760 DOI: 10.1099/00221287-91-1-167] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Nine volatile hydrocarbons, as well as methyl chloride, carbonyl sulphide and carbon disulphide, have been identified by mass spectrometry as products of Agaricus bisporus in the compost used in comerical mushroom beds. Of these, only ethylene showed a pattern of production that could be correlated with developmental phases of the crop, high levels being produced whenever fruit bodies were rapidly enlarging. In laboratory flask cultures, under controlled conditions, high levels of ethylene occurred whenever young fruit bodies entered the expansion phase. The enhanced rate of ethylene production continued over several days, irrespective of whether fruit bodies were removed. Production occurred within the colonized compost; no ethylene was evolved by the fruit body itself. When the first fruit bodies expanded, either in beds or culture flasks, laccase levels in the compost fell and those of a beta-1,4-glucanase (cellulase) rose. The enzyme switch occurred once only, during maturation of the first fruit bodies, whereas an elevated ethylene production was associated with each occasion when fruit body maturation took place. The low level of laccase and high of cellulase characterized the whole of the reproductive stage of A. bisporus, whereas the phasic periods of high ethylene production distinguished between periods of fruit body maturation and intervening resting periods.
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Abstract
A rapid sugar fermentation procedure has been developed for the confirmation of Neisseria gonorrhoeae from either primary isolation media or purification media. A lightly buffered salt solution with pH indicator and sugars was heavily inoculated with presumptively positive growth. Proper fermentation patterns are obtained in 1 to 4 h with no interference from inhibited contaminants or variation in results due to differing growth requirements of gonococcal strains.
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Brooks JB, Kellogg DS, Thacker L, Turner EM. Analysis by gas chromatography of hydroxy acids produced by several species of Neisseria. Can J Microbiol 1972; 18:157-68. [PMID: 4622986 DOI: 10.1139/m72-026] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A new technique, which uses formation of double derivatives for the detection of hydroxy acids in spent cultural media by gas–liquid chromatography (g.l.c), is described. The method is practical enough for use in routine analysis. Fourteen species of the genus Neisseria, including several serogroups of N. meningitidis, were tested. Four hydroxy acids and a keto acid which have not been previously reported in Neisseria were tentatively identified from acidified ether extracts of spent cultural media on both polar and nonpolar columns. Different g.l.c. profiles were obtained for several serogroups of N. meningitidis, N. gonorrhoeae, N. haemolysans, N. lactamicus, N. perflava, N. flava, N. mucosa, N. catarrhalis, N. ovis, and N. caviae. Strains of N. meningitidis, N. subflava, N. flavescens, N. caviae, and N. catarrhalis comprise a heterogeneous group. One strain previously identified as N. caviae gave a g.l.c. profile like that of N. ovis. The data indicate that g.l.c. analysis of metabolic products provides information necessary for differentiating many members of the genus.
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Brooks JB, Kellogg DS, Thacker L, Turner EM. Analysis by gas chromatography of fatty acids found in whole cultural extracts of Neisseria species. Can J Microbiol 1971; 17:531-43. [PMID: 5102782 DOI: 10.1139/m71-088] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Sixty-five strains of Neisseria were tested. They included 12 species and several serogroups of N. meningitidis. A variety of acids, including keto acids, were detected by gas chromatography. Many of the acids detected have not been previously reported. Strains of N. meningitidis and N. catarrhalis were found to comprise a heterogeneous group. Cultures of N. flavescens, N. sicca, N. subflava, N. perflava, and N. cinerea produced acid patterns like N. meningitidis serogroup B. N. flava and N. mucosa were also like this group except that phenylpyruvic acid was detected in cultures of the former organisms. Strains of N. gonorrhoeae differed from strains of N. meningitidis in that acetic acid was produced, propionic acid was not used, and only a moderate amount of α-ketoisocaproic acid was detected. Strains of N. lactamicus, N. haemolysans, N. ovis, and N. catarrhalis also produced characteristic patterns that distinguished them from other species tested. The data indicate that criteria in addition to those now routinely used should be established to identify some members of the genus properly.
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