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Objective:To investigate the use of the Computer Rod and Frame (CRAF) Test in a clinical environment as a means of measuring errors in the perception of vertical in subjects with neck pain.Design:Comparison of vertical alignment errors generated using the CRAF in two groups of subjects with neck pain, compared to an asymptomatic control group.Setting:Two urban chiropractic clinics in the UK.Patients:New patients with neck pain as the primary complaint classified according to traumatic (n = 26) or insidious (n = 45) onset of their neck pain. Seventeen asymptomatic subjects formed a control group.Intervention:Subjects were tested before treatment. They viewed a display of a tilted rod on a plain dark background through head mounted video glasses. The task was to use the mouse to align the rod to vertical in the presence or absence of a surrounding frame.Main outcome measures:Errors in rod alignment measured to an accuracy of 0.5 degrees.Results:In the asymptomatic group, tilting the frame 15 degrees from the horizontal caused significant errors in alignment of the rod. The mean and range of absolute alignment errors were greater in the neck pain patient groups than controls, although this did not reach statistical significance. Classification of the absolute errors by size, 2.5 degrees, suggested a possible association between neck pain and alignment error in a subgroup of subjects.Conclusion:This pilot study has demonstrated that the CRAF Test provides a practical method for assessing disturbances of the perception of vertical within a clinical practice setting. The results indicate that there may be a subpopulation of patients in which neck pain is associated with reduced performance on this test. [ABSTRACT FROM AUTHOR]

Phytase enzymes are a crucial component of the natural phosphorus cycle, as they help make phosphate bioavailable by releasing it from phytate, the primary reservoir of organic phosphorus in grain and soil. Phytases also comprise a significant segment of the agricultural enzyme market, used primarily as an animal feed additive. At least four structurally and mechanistically distinct classes of phytases have evolved in bacteria and eukaryotes, and the natural diversity of each class is explored here using advances in protein structure prediction and functional annotation. This graphical review aims to provide a succinct description of the major classes of phytase enzymes across phyla, including their structures, conserved motifs, and mechanisms of action., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Isoprene monooxygenase (IsoMO, encoded by isoABCDEF ) initiates the oxidation of the climate-active gas isoprene, with the genes isoGHIJ and aldH nearly always found adjacent to isoABCDEF in extant and metagenome-derived isoprene degraders. The roles of isoGHIJ and aldH are uncertain, although each is essential to isoprene degradation. We report here the characterization of these proteins from two model isoprene degraders, Rhodococcus sp. strain AD45 and Variovorax sp. strain WS11. The genes isoHIJ and aldH from Variovorax and aldH from Rhodococcus were expressed individually in Escherichia coli as maltose binding protein fusions to overcome issues of insolubility. The activity of two glutathione S -transferases from Variovorax , IsoI and IsoJ was assessed with model substrates, and the conversion of epoxyisoprene to the intermediate 1-hydroxy-2-glutathionyl-2-methyl-3-butene (HGMB) was demonstrated. The next step of the isoprene metabolic pathway of Variovorax is catalyzed by the dehydrogenase IsoH, resulting in the conversion of HGMB to 2-glutathionyl-2-methyl-3-butenoic acid (GMBA). The aldehyde dehydrogenases (AldH) from Variovorax and Rhodococcus were examined with a variety of aldehydes, with both exhibiting maximum activity with butanal. AldH significantly increased the rate of production of NADH when added to the IsoH-catalyzed conversion of HGMB to GMBA (via GMB), suggesting a synergistic role for AldH in the isoprene metabolic pathway. An in silico analysis of IsoG revealed that this protein, which is essential for isoprene metabolism in Variovorax , is an enzyme of the formyl CoA-transferase family and is predicted to catalyze the formation of a GMBA-CoA thioester as an intermediate in the isoprene oxidation pathway. IMPORTANCE Isoprene is a climate-active gas, largely produced by trees, which is released from the biosphere in amounts equivalent to those of methane and all other volatile organic compounds combined. Bacteria found in many environments, including soils and on the surface of leaves of isoprene-producing trees, can grow on isoprene and thus may represent a significant biological sink for this globally significant volatile compound and remove isoprene before it escapes to the atmosphere, thus reducing its potency as a climate-active gas. The initial oxidation of isoprene by bacteria is mediated by isoprene monooxygenase encoded by the genes isoABCDEF . In isoprene-degrading bacteria, a second gene cluster, isoGHIJ , is also present, although the exact role in isoprene degradation by the proteins encoded by these genes is uncertain. This investigation sheds new light on the roles of these proteins in the isoprene oxidation pathway in two model isoprene-degrading bacteria of the genera Rhodococcus and Variovorax.

Bacteria that inhabit soils and the leaves of trees partially mitigate the release of the abundant volatile organic compound, isoprene (2-methyl-1,3-butadiene). While the initial steps of isoprene metabolism were identified in Rhodococcus sp. AD45 two decades ago, the isoprene metabolic pathway still remains largely undefined. Limited understanding of the functions of isoG, isoJ and aldH and uncertainty in the route of isoprene-derived carbon into central metabolism have hindered our understanding of isoprene metabolism. These previously uncharacterised iso genes are essential in Variovorax sp. WS11, determined by targeted mutagenesis. Using combined 'omics-based approaches, we propose the complete isoprene metabolic pathway. Isoprene is converted to propionyl-CoA, which is assimilated by the chromosomally encoded methylmalonyl-CoA pathway, requiring biotin and vitamin B12, with the plasmid-encoded methylcitrate pathway potentially providing robustness against limitations in these vitamins. Key components of this pathway were induced by both isoprene and its initial oxidation product, epoxyisoprene, the principal inducer of isoprene metabolism in both Variovorax sp. WS11 and Rhodococcus sp. AD45. Analysis of the genomes of distinct isoprene-degrading bacteria indicated that all of the genetic components of the methylcitrate and methylmalonyl-CoA pathways are not always present in isoprene degraders, although incorporation of isoprene-derived carbon via propionyl-CoA and acetyl-CoA is universally indicated., (© 2022 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.)

Phylogenetic analysis, homology modelling and biochemical methods have been employed to characterize a phytase from a Gram-negative soil bacterium. Acinetobacter sp. AC1-2 phytase belongs to clade 2 of the histidine (acid) phytases, to the Multiple Inositol Polyphosphate Phosphatase (MINPP) subclass. The enzyme was extraordinarily stable in solution both at room temperature and 4°C, retaining near 100% activity over 755 days. It showed a broad pH activity profile from 2-8.5 with maxima at 3, 4.5-5 and 6. The enzyme showed Michaelis-Menten kinetics and substrate inhibition (Vmax, Km, and Ki, 228 U/mg, 0.65 mM and 2.23 mM, respectively). Homology modelling using the crystal structure of a homologous MINPP from a human gut commensal bacterium indicated the presence of a potentially stabilising polypeptide loop (a U-loop) straddling the active site. By employ of the enantiospecificity of Arabidopsis inositol tris/tetrakisphosphate kinase 1 for inositol pentakisphosphates, we show AC1-2 MINPP to possess D6-phytase activity, which allowed modelling of active site specificity pockets for InsP6 substrate. While phytase gene transcription was unaltered in rich media, it was repressed in minimal media with phytic acid and orthophosphate as phosphate sources. The results of this study reveal AC1-2 MINPP to possess desirable attributes relevant to biotechnological use., Competing Interests: The authors have declared that no competing interests exist.

HPLC methods are shown to be of predictive value for classification of phytase activity of aggregate microbial communities and pure cultures. Applied in initial screens, they obviate the problems of 'false-positive' detection arising from impurity of substrate and imprecision of methodologies that rely on phytate-specific media. In doing so, they simplify selection of candidates for biotechnological applications. Combined with 16S sequencing and simple bioinformatics, they reveal diversity of the histidine phosphatase class of phytases most commonly exploited for biotechnological use. They reveal contribution of multiple inositol-polyphosphate phosphatase (MINPP) activity to aggregate soil phytase activity, and they identity Acinetobacter spp. as harbouring this prevalent soil phytase activity. Previously, among bacteria MINPP was described exclusively as an activity of gut commensals. HPLC methods have also identified, in a facile manner, a known commercially successful histidine (acid) phosphatase enzyme. The methods described afford opportunity for isolation of phytases for biotechnological use from other environments. They reveal the position of attack on phytate by diverse histidine phosphatases, something that other methods lack., (© 2020 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Objective: To describe the case of a patient diagnosed with neuralgic amyotrophy (NA) illustrating pertinent aspects of differential diagnosis, the use of clinical neurophysiological procedures to aid in establishing the diagnosis, and issues of management., Clinical Features: A 39-year-old male soldier presented with a rapid onset of marked loss of left shoulder movement. This started acutely early one morning as a sharp, severe lower neck pain progressing over the following 2 weeks to a less severe dull ache in the left shoulder and arm. Pain was rapidly replaced with weakness. Physical examination and electrodiagnostic investigation helped establish a diagnosis of NA., Intervention and Outcome: The patient was reassured that this is normally a self-limiting condition. Range of motion exercises progressing to a strengthening program was prescribed. He was progressing well; however, we lost contact because of his commitments in the armed service., Conclusion: When a patient presents with shoulder and arm pain of neurogenic origin, NA should be a consideration. Differentiating NA from radiculopathy is especially important in making management decisions. With a careful history and physical examination, the diagnosis may be made without the need for ancillary investigations. Neuralgic amyotrophy is a self-limiting condition requiring reassurance and monitoring.

Objective: To investigate cervicocephalic kinesthetic sensibility (head repositioning accuracy to subjective straight ahead) in patients with chronic, nontraumatic cervical spine pain., Design: A prospective, 2-group, observational design., Setting: An outpatient chiropractic clinic in the United Kingdom., Participants: Eleven patients (6 men, 5 women; mean age +/- standard deviation, 41.1 +/- 13.3 yr; range, 18-55 yr) with chronic, nontraumatic cervical spine pain (mean duration, 24 +/- 18 mo), with no evidence of cervical radiculopathy and/or myelopathy or any other neurologic disorder. Eleven asymptomatic, unimpaired volunteers (5 men, 6 women; mean age, 39.3 +/- 10.3 yr; range, 28-54 yr) with no history of whiplash or other cervical spine injury or pain served as controls., Main Outcome Measures: Cervicocephalic kinesthetic sensibility was investigated by testing the ability of blindfolded participants to relocate accurately the head on the trunk, to a subjective straight-ahead position, after a near-maximal active movement of the head in the horizontal or vertical plane. The active cervical range of motion and the duration and intensity of neck pain were also recorded., Results: Mann-Whitney U testing indicated that the patient (P) group was no less accurate in head repositioning than the control (C) group for all movement directions except flexion (median global positioning error [95% confidence interval], P = 5.7 degrees [5.03-9.10], C = 4.2 degrees [3.17-5.32]; p <.05)., Conclusions: Nontraumatic neck pain patients show little evidence of impaired cervicocephalic kinesthetic sensibility. These results contrast with studies of chronic cervical pain patients in which the origin was not controlled or involved a cervical whiplash injury., (Copyright 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation)