Factor 1 Research Articles

QLIF-33. ACTIVE COPING STRATEGIES ARE ASSOCIATED WITH IMPROVED OVERALL SURVIVAL IN NEWLY DIAGNOSED GLIOBLASTOMA: A PROSPECTIVE STUDY

The impact of psychosocial variables on the survival of cancer is discussed controversially. In a prospective study, we investigated whether the quality of coping strategies are of prognostic value in newly diagnosed glioblastoma. In a prospective study, patients with newly diagnosed glioblastoma underwent audiotaped interviews immediately following surgery and before initiating radiochemotherapy. The patients’ coping strategies were then identified from each interview using the Ulm Coping Manual that describes 34 different coping strategies. An exploratory factor analysis was conducted to assess patterns of coping strategies that reflect the same underlying general coping mechanism (also known as factor). These factors are characterized by a set of highly correlated coping strategies. Patients who are highly associated (loaded highly on) with a specific factor were compared against those with low loadings. We compared overall survival (OS) between patients loading highly on a specific factor and those with negative loadings. A Cox regression analysis served to detect independent prognostic variables. Eighteen patients were eligible for interviewing. Six factors have been retained based on the amount of variation they explain in all coping strategies. Among those, factor 1 (F1) explained the overall highest amount of variation and was characterized almost exclusively by high loadings of active coping strategies, including taking the initiative, problem analysis, emotional support, optimism/hope, and active compliance with factor loadings ranging from 54%-92%. The high F1 loadings group had a particularly high median OS (24.1 months) as compared to the one with low F1 loadings (median OS, 10.6 months, p=0.0002). In a multivariable Cox regression analysis, F1 emerged as a prognostic factor (p<0.001) independent of canonical prognostic markers including age, Karnofsky performance score, extent of resection, and O6-methylguanin-DNA-methyltransferase (MGMT). Exploitation of coping mechanisms may offer a possible novel avenue for glioblastoma treatment. Further exploration in a larger trial is warranted.

Spatial variability of physical properties: relationship with relief, organic matter and productivity in Conilon coffee

Soil attributes may be influenced by the relief generating homogeneous productivity zones. From this hypothesis, we identified soil attribute groups, its spatial variability and relationship with productivity and relief by Factor Analysis (FA) and geostatistics methods. The study was conducted in a Oxisol cultivated with Conilon coffee in the State of Espirito Santo. The AF group in Factor 1 (F1) attributes related to soil aggregation was not associated with relief and productivity. Its spatial variability is influenced by management as showed by the lower spatial continuity and dependence in 0 – 0.10 m depth and by pure nugget effect in 0.10 – 0.20 m depth. From the factor 2 (F2), obtained in two depths, can be grouped soil attributes related to water retention, mainly the clay, microporosity and moisture which together increase at a higher altitude and lower slope where occur higher productivity areas. The spatial variability of F2 indicates greater continuity and spatial dependence, suggesting influence of relief in the spatial variation structure.

Trends and practices of consumers buying online and offline

Purpose – The purpose of this paper is to assess the trends and practices of consumers buying their products online and offline. Further, it also analyses the factors which influence consumers to go online and offline for their purchases. Design/methodology/approach – To analyse the factors influencing consumer’s buying behaviour, 18 variables have been identified and questionnaire using a seven-point scale (where 1 indicating very unimportant and 7 very important) was designed. It was circulated among 875 consumers residing in Delhi and National Capital Region between February 2012 and April 2012, who buy offline or online or from both sources. The responses so collected have been tabulated and analysed with the help of a factor analysis method. The principal component method has been used to determine the minimum number of factors that would account for the maximum variance in the data collected. The data have been analysed by using SPSS version 19. Findings – The study identifies Factor 1 (F1) as a Pre...

Psychopathy factor interactions and co-occurring psychopathology: Does measurement approach matter?

The 2 dimensions of psychopathy as operationalized by various measurement tools show differential associations with psychopathology; however, evidence suggests that the statistical interaction of Factor 1 (F1) and Factor 2 (F2) may be important in understanding associations with psychopathology. Findings regarding the interactive effects of F1 and F2 are mixed, as both potentiating and protective effects have emerged. Moreover, approaches to measuring F1 (e.g., clinical interview vs. self-report) are based on different conceptualizations of F1, which may influence the interactive effects. The current study aims to (a) elucidate the influence of F1 and F2 on psychopathology by using both variable-centered and person-centered approaches and (b) determine whether the measurement of F1 influences the interactive effects of F1 and F2 by comparing the strength of interactive effects across F1 measures in a sample of over 1,500 offenders. Across analytic methods, there were very few cases in which F1 statistically influenced the association between F2 and psychopathology, such that F1 failed to evidence either potentiating or protective effects on F2. Furthermore, the conceptualization of F1 across psychopathy measures did not impact the interactive effects of F1 and F2. These findings suggest that F2 is probably driving the relations between psychopathy and other forms of psychopathology and that F1 may play less of a role in interacting with F2 than previously believed.

Kefahaman Konsep Asas Dialog Antara Agama di Kalangan Ketua Agama Islam dan Kristian di Malaysia dan Kesannya Terhadap Hubungan Sosial

The objective of this study is to, (1) measure level of understanding of religious leader (Islam and Christianity) on the basic concept of interfaith dialogue, (2) analyse the factors of the understanding developed and (3) analyse its effects on their social relation. This study uses the purposive sampling method in determining the appropriate respondents and total respondents for Islam dan Christianity which are 36 and 37 respectively. The authors use the method of questionnaire in collecting data and Likert Scale (1-5) in measuring the level of understanding and its effect, which is developed as the Skala Tahap Kefahaman Dialog (STKD) and Skala Kesan Hubungan Sosial (SKHS). The authors also use the Fixed Comparison Method and the Matrix Analysis in analysing the collected data, whereby the results were descriptive in nature. A major conclusion that could be drawn from the study is, (1) the level of understanding between Muslim and Christian Religious Leaders on the basic concept of the interfaith dialogue is equal as both are in the category of “Faham (F)” the fourth level of the Skala Tahap Kefahaman Dialog (STKD). (2) The main factors which contribute to this understanding are (a) Factor 1 (F1): level of education/formal education on religion, (b) Factor 2 (F2): past experience in interfaith dialogue activities and (c) Factor 3 (F3): level of respondent religiosity. (3) Even though the level of understanding is equal for both groups of respondents but the Christian Religious Leader has a higher scale “Tinggi(T)” on the effects of the understanding towards social relation in comparison to the Muslim Religious Leader whose level of understanding is in the mid-level of “Sederhana (SD)” based on the Skala Kesan Hubungan Sosial (SKHS). Using the Matrix Analysis, the result shows that there is a correlation between the ISSN: 2201-6333 (Print) ISSN: 2201-6740 (Online) www.ijern.com 2 understandings on the interfaith dialogue basic concepts with the respondents’ social relation but it is contributed by different factors for every group of respondents. Thus, this study has found that Factor 4 (F4): Factor of Current Policy (Organization) has a heavy weightage which forms an overall average impact to the Muslim Religious Leader’s social relation only in the scale of “Sederhana (SD)”. On the other hand, the Christian Religious Leader scored “Tinggi(T)” for their social relation which is contributed by Factor 1 (F1): level of education / formal education on religion and Factor 4 (F4): Factor on the Current Policy (Organization).

Regional assessment of ambient volatile organic compounds from biopharmaceutical R&D complex

Biopharmaceutical R&D complexes are major emission sources of volatile organic compounds (VOCs), which may pose potential health risks for staff on site and residents nearby. In this paper health risk assessments were performed for the VOCs in the ambient air of a typical biopharmaceutical R&D complex in China. Results showed halogenated and alkyl compounds were dominant components among 24 major VOCs from 9 selected sampling sites, inside or around the complex. The principal component analysis (PCA) indicated VOCs were generated predominantly from the biopharmaceutical research activities (factor 1 (F1), 71.6%) and traffic vehicles (factor 2 (F2), 15.4%), which were confirmed by contour maps of five selected VOCs (benzene, toluene, chlorobenzene, methylene chloride and n-hexane) simulated by Golden Software Surfer. The cumulative cancer risks for the staff on site and residents nearby were investigated and results showed the risk value were 1.01E−5 and 2.03E−5, respectively, higher than the threshold value of 1.0E−6. These results indicated that elevated VOCs from biopharmaceutical R&D complex are potential risks to the public health. Furthermore, the human health risk assessment revealed that 1,2-dichloroethane, methylene chloride, carbon tetrachloride and benzene were the dominant risk contributors for staff on site, while methyl chloride, carbon tetrachloride, 1,2-dichloroethane and tetrahydrofuran for residents nearby. As a conclusion, this work suggests that proper control strategy should be taken for VOCs releasing to minimize the public health risks, especially for the halogenated compounds.

Uses and abuses of the Hare Psychopathy Checklist

Notions of psychopathic personality and personality disorder have a lengthy history within criminal justice and mental health settings. Issues of how to assess and intervene with this group of individuals...

The Levenson Self-Report Psychopathy Scale

There are several self-report measures of psychopathy, most of which use a two-factor structure. There is debate regarding the convergence of these factors, particularly with regard to Factor 1 (F1), which is related to the interpersonal and affective aspects of psychopathy; Factor 2 (F2) is related to the social deviance associated with psychopathy. This study examines the relations between the Levenson Self-Report Psychopathy (LSRP) factors and personality traits and disorders (PDs) in an undergraduate sample (n = 271). LSRP Factor 1 is related to an antagonistic interpersonal style (i.e., low Agreeableness; high Narcissistic PD and ratings of prototypical psychopathy), whereas Factor 2 is more strongly related to negative emotionality (i.e., Neuroticism), disinhibition (i.e., low Conscientiousness) and a broad array of PD symptoms. The authors interpret these findings in the context of alternative measures of psychopathy and suggest that the LSRP is a reasonable, albeit imperfect, measure of psychopathy.

Factors associated with life satisfaction in Japanese stroke outpatients

Purpose. To measure life satisfaction in Japanese stroke outpatients and randomly-sampled community residents and to investigate variables influencing their life satisfaction.Method. Data on the demographic and clinical profiles, Satisfaction in Daily Life (SDL), other measurements, were obtained from 869 stroke outpatients (552 males, 317 females) and 748 community-dwelling elderly (360 males, 388 females), aged 55 years and older. Differences in categorical variables and continuous variables were tested by chi-square test and ANCOVA with age as the covariate, respectively.Results. The 11 SDL items were subjected to a factor analysis, which extracted two factors. Factor 1 (F1), labeled as ‘satisfaction with one's own abilities’, included satisfaction with housework, self-care, gait, physical health, hobby and leisure, social intercourse and mental health. Factor 2 (F2), ‘satisfaction with external factors’, included satisfaction with partner/family relationship, economic state and social security, and house facilities. Both F1 and F2 scores were significantly lower for stroke outpatients (M = 19.7 and 10.9, respectively) than for community-dwelling elderly (M = 28.2 and 12.0, respectively) (p < 0.001). Living conditions were significantly associated with F2, but not with F1. Males living alone scored lowest on F2 than the others for both groups. Among stroke outpatients, both F1 and F2 scores differed significantly by the type of hemiparesis and the severity of aphasia.Conclusions. SDL of stroke outpatients, which was lower than community-dwelling elderly, differed by the type of hemiparesis, the severity of aphasia, and living conditions. The effects of living conditions might vary with gender.

Summertime aerosol chemical components in the marine boundary layer of the Arctic Ocean

Samples of aerosols from the marine boundary layer of the Arctic Ocean were collected aboard the R/V Xuelong during summer on the Second Chinese Arctic Research Expedition (July–September 2003). Synchrotron radiation X‐ray fluorescence (SR‐XRF) was used to determine chemical compositions of aerosol particles. Multivariate analysis of the SR‐XRF data resolved a number of components (factors), which, on the basis of their chemical compositions and from their affiliation with specific meteorological flow patterns, were assigned physical meanings. Five factors explaining 94.7% of the total variance were identified. Ship emissions accounted for 35.3% of the variance (factor 1 (F1)) and are loaded significantly with S, Fe, V, and Ni. The total Fe emitted from ships globally was estimated at 8.60 × 106 kg yr−1. Heavy‐metal‐rich factors included 34.0% of the variance (F2 and F3) and were interpreted to be pollution carried into the Arctic Ocean by long‐range transport. Anthropogenic contributions from industrial regions to the Arctic Ocean during the summer vary and depend on the source locations. Air mass backward trajectories indicate that the metals including Hg, Pb, Cu, and Zn come mainly from northern Russia. The third source controlling the chemical compositions of aerosols was sea salt (F4, 12.8%). The role of sea salt decreased from the open sea to areas near pack ice. On the basis of the factor scores of aerosol samples, we infer that chlorine volatilization from sea salt may occur, enhanced by nitrogen and sulfur contamination emitted from ships. Because the global inventories of nitrogen and sulfur for ship exhausts are large, and halogens could have important consequences in possible tropospheric ozone destruction, the role of ships in influencing halogen depression in sea salt should be further investigated. Finally, we also identified a crustal factor (F5, 12.6%) and suggest that crustal elements (e.g., Ca) contaminating sea ice may become reinjected into the atmosphere as windblown aerosols.

Membrane Association, Mechanism of Action, and Structure of Arabidopsis Embryonic Factor 1 (FAC1)

Embryonic factor 1 (FAC1) is one of the earliest expressed plant genes and encodes an AMP deaminase (AMPD), which is also an identified herbicide target. This report identifies an N-terminal transmembrane domain in Arabidopsis FAC1, explores subcellular fractionation, and presents a 3.3-A globular catalytic domain x-ray crystal structure with a bound herbicide-based transition state inhibitor that provides the first glimpse of a complete AMPD active site. FAC1 contains an (alpha/beta)(8)-barrel characterized by loops in place of strands 5 and 6 that places it in a small subset of the amidohydrolase superfamily with imperfect folds. Unlike tetrameric animal orthologs, FAC1 is a dimer and each subunit contains an exposed Walker A motif that may be involved in the dramatic combined K(m) (25-80-fold lower) and V(max) (5-6-fold higher) activation by ATP. Normal mode analysis predicts a hinge motion that flattens basic surfaces on each monomer that flank the dimer interface, which suggests a reversible association between the FAC1 globular catalytic domain and intracellular membranes, with N-terminal transmembrane and disordered linker regions serving as the anchor and attachment to the globular catalytic domain, respectively.

Impulsivity and time estimation: Casting a net to catch a fish

We employed a series of time-estimation tasks, chosen such that impulsivity could be revealed in deviant performance both within and between tasks. Trait impulsivity was assessed using a number of measures; cognitive impulsivity was measured using a number of neuropsychological tests (e.g., Trail Making, Circle Tracing). Time estimation was evaluated using reproduction tasks (both remote and immediate) within a prospective paradigm. The structure underlying the data is four-dimensional: Factor 1 (F1) has contributions from both venturesomeness and the indices of immediate time reproduction, implicating sensation seeking; F2 is uniquely identified with performance on remote time reproduction; F3 implicates a component of trait impulsivity; F4 implicates a component of cognitive-motor impulsivity.

EMBRYONIC FACTOR 1 encodes an AMP deaminase and is essential for the zygote to embryo transition in Arabidopsis

Fusion of the egg and the sperm cells in plants produces a zygote that develops into an embryo. Screening of ethyl methanesulfonate-mutagenized populations of Arabidopsis led to the identification of EMBRYONIC FACTOR 1 (FAC1), a locus that gives a zygote-lethal phenotype when mutated. The FAC1 gene was identified by positional cloning and confirmed by a genetic complementation test against a T-DNA insertion allele. It encodes an AMP deaminase (AMPD) that is known in human and yeast to convert AMP to IMP to maintain the energy potential. Expression of FAC1 in a yeast AMPD mutant after removal of its N-terminal putative transmembrane domain complemented the mutant phenotype, suggesting a functional conservancy but a structural divergence through evolution. Although a low level of FAC1 expression was observed in all organs tested, using a reporter construct we observed a significantly increased FAC1 expression in the zygote, early embryo and endosperm. Furthermore, during somatic embryogenesis, a high level of FAC1 expression was observed in developing embryos including putative embryogenic cells. FAC1, therefore, represents one of the earliest expressed genes known in plants. It may act through AMP depletion to provide sufficient energy for the zygote to proceed through development.

Coupling factor 1 from Escherichia coli lacking subunits .delta. and .epsilon.: preparation and specific binding to depleted membranes, mediated by subunits .delta. or .epsilon.

A procedure for the preparation of coupling factor 1 (F1) from Escherichia coli lacking subunits delta and epsilon is described. Using chloroform and dimethyl sulfoxide, we can isolate F1 containing only subunits alpha, beta, and gamma [F1(alpha beta gamma)] directly from membrane vesicles in 10-mg quantities. Pure and active subunits delta and epsilon were prepared from five-subunit F1 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After addition of these subunits, F1(alpha beta gamma) is as active in reconstituting ATP-dependent transhydrogenase as five-subunit F1. The ATPase activity of F1 (alpha beta gamma) is inhibited by subunit epsilon in a 1:1 stoichiometry to the same extent (approximately equal to 90%) and with the same affinity (Ki = 0.2-0.8 nM) as reported earlier [Dunn, S.D. (1982) J. Biol. Chem. 257, 7354-7359]. In the presence of either delta or epsilon, F1(alpha beta gamma) binds to F1-depleted membrane vesicles and to liposomes containing the membrane sector (F0) of the ATP synthase to an extent commensurate with the F0 content. The binding ratios epsilon/F1 (alpha beta gamma) and probably also delta/F1 (alpha beta gamma) are close to unity. The specific, delta- or epsilon-deficient F1.F0 complexes presumably formed show ATPase activities sensitive to subunit epsilon but not to dicyclohexylcarbodiimide, and no energy-transfer capabilities. Binding studies at different pH values suggest that F1-F0 interactions in the presence of both subunits delta and epsilon are similar to a combination of those mediated by delta or epsilon alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Purification and properties of the proton-translocating adenosine triphosphatase complex of bovine heart mitochondria.

1. The proton-translocating adenosine triphosphatase (ATPase) of bovine heart mitochondria was highly purified by extraction of submitochondrial particles with cholate, fractionation with ammonium sulfate, and sucrose gradient centrifugation in the presence of methanol, deoxycholate, and lysolecithin. 2. The preparation had a very low content of phospholipids, respiratory components, and adenine nucleotide transporter. The ATPase activity (14 o 16 micromoles/min/mg at 30 degrees) was dependent on addition of phospholipids. The purified enzyme was reconstituted with phospholipids, coupling factor 1 (F1), and the oligomycin sensitivity-conferring protein (OSCP) yielding vesicles with highly active 32Pi-ATP exchange (up to 260 nanomoles/min/mg at 30 degrees), and a proton pump driven by ATP. Site III oxidative phosphorylation was reconstituted when purified cytochrome oxidase was included. 3. The 32Pi-ATP exchange of the reconstituted vesicles was sensitive to both rutamycin and dichylohexylcarbodiimide but the ATPase activity was sensitive to rutamycin and not to dicyclohexylcarbodiimide. 4. In sodium dodecyl sulfate-acrylamide gel scans of the complex, the subunits of F1, OSCP, and three other major bands with apparent molecular weights of 32,000, 23,000, and about 11,000 were noted. Three other minor bands with estimated molecular weights of 80,000, 70,000, and 52,000 were also detected. These bands apparently represent residual trace amounts of respiratory components. Quantitative assays of individual respiratory components revealed between 0 and 3% contamination. 5. We conclude that the rutamycin-sensitive ATPase complex functions as a reversible ATP-driven proton pump.

Assembly of the Mitochondrial Membrane System: V. PROPERTIES OF A DISPERSED PREPARATION OF THE RUTAMYCIN-SENSITIVE ADENOSINE TRIPHOSPHATASE OF YEAST MITOCHONDRIA

Abstract The rutamycin-sensitive adenosine triphosphatase (ATPase) complex has been solubilized from yeast submitochondrial particles with Triton X-100 and further purified by centrifugation on a glycerol gradient. The purified enzyme is dispersed and by electron microscopic criteria appears to be an oval-shaped globular particle 100 by 150 A. Both the cold-labile ATPase, coupling factor 1 (F1) and the rutamycin-sensitive complex have been analyzed for their subunit protein composition and their molecular weights by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The results of these analyses indicate that F1 contains five different subunit proteins. The two major subunits of F1 have molecular weights of 58,500 and 54,000. The rutamycin-sensitive complex contains all of the components of F1 and four additional proteins. The composite molecular weight of the proteins specific to the complex is approximately 100,000. Two lines of evidence indicate that the subunit proteins seen on polyacrylamide gels are intrinsic components of the complex. The ATPase complex reconstituted from F1, oligomycin sensitivity-conferring protein, and depleted membranes has been shown to contain all of the subunits seen in the native enzyme. Secondly, antibody prepared against F1 cause the nine subunits of the complex to precipitate.

Biochemical Adaptations in Muscle: II. RESPONSE OF MITOCHONDRIAL ADENOSINE TRIPHOSPHATASE, CREATINE PHOSPHOKINASE, AND ADENYLATE KINASE ACTIVITIES IN SKELETAL MUSCLE TO EXERCISE

Abstract It was previously found that the enzymes of the mitochondrial respiratory chain increase in leg muscles of rats subjected to a program of running. The results of the present study provide evidence that mitochondrial coupling factor 1 (F1) is increased in proportion to the constituents of the respiratory chain in muscle that has adapted to endurance exercise. The oligomycin-sensitive adenosine triphosphatase (ATPase) activity of the mitochondrial fraction of muscle, after disruption of the mitochondria and unmasking of the latent ATPase activity, was used as a measure of F1. The concentration of cytochrome c was used as a marker for the respiratory chain. Both mitochondrial ATPase and cytochrome c increased 2-fold in gastrocnemius muscle in response to a running program, suggesting that a coordinated, quantitatively related increase in these components of the mitochondrial cristae occurs during the adaptation to exercise. In contrast, the levels of activity of mitochondrial creatine phosphokinase and adenylate kinase did not increase, providing evidence of a change in mitochondrial composition. Cytoplasmic creatine phosphokinase and adenylate kinase activities were also unchanged. These findings reinforce previous evidence indicating that endurance exercise results in an adaptive increase in the capacity of muscle to regenerate ATP aerobically, whereas the ability to form ATP by anaerobic mechanisms is unaffected.

A soluble mitochondrial ATP synthetase complex catalyzing ATP-phosphate and ATP-ADP exchange.

The highly purified soluble ATP synthetase complex from mitochondria, containing energy-transfer Factor A (the terminal ADP phosphorylation enzyme of oxidative phosphorylation) and Factor D, catalyzes ATP-P(i) and ATP-ADP exchange reactions. The ATP-P(i) exchange activity is inhibited by low concentrations of the uncouplers of oxidative phosphorylation, oligomycin and p-chloromercnriphenylsulfonate. It is stimulated threefold by dithiothreitol and is Mg(++) dependent. Antiserum to coupling factor 1 (F(1)) also inhibits the ATP-P(i) exchange. The ATP-ADP exchange activity appears to be greater than the ATP-P(i) exchange activity. The results suggest that the nonphosphorylated high-energy intermediate (X approximately C), and possibly the phosphorylated intermediate (X approximately P), are formed on the synthetase. Sites of uncoupler and oligomycin action reside in the terminal ATP synthetase.

Partial Resolution of the Enzymes Catalyzing Oxidative Phosphorylation: XIV. INTERACTION OF PURIFIED MITOCHONDRIAL ADENOSINE TRIPHOSPHATASE FROM BAKERS' YEAST WITH SUBMITOCHONDRIAL PARTICLES FROM BEEF HEART

Abstract 1. A Mg++-dependent adenosine triphosphatase was solubilized and purified from bakers' yeast mitochondria. The enzyme resembled mitochondrial ATPase from beef heart with respect to substrate specificity, cold lability, and other physical properties. 2. An antiserum against the purified yeast enzyme inhibited the ATPase activity of the soluble enzyme as well as ATPase and oxidative phosphorylation in submitochondrial yeast particles. Mitochondrial ATPase from beef heart or from Neurospora crassa was not inhibited by the antiserum. 3. Submitochondrial beef heart particles devoid of endogenous ATPase could bind the purified yeast enzyme without changing its immunological specificity. The ATPase activity of the resultant hybrid particles, like that of beef heart particles, was strongly inhibited by low levels of rutamycin. In contrast, submitochondrial particles from yeast were much less sensitive to this inhibitor. 4. The yeast enzyme stimulated oxidative phosphorylation in beef heart particles which were deficient in, but not devoid of, endogenous ATPase. The stimulation was dependent on the presence of beef heart coupling factor 1 (F1) in these particles and was unaffected by the antiserum against the yeast enzyme. Antiserum against beef heart F1 strongly inhibited phosphorylation. These results suggest that yeast F1, in contrast to beef heart F1, does not significantly participate in phosphate transfer reactions when it functions as a coupling factor in beef heart particles. Rather, it is proposed that the stimulation by yeast F1 is due to an effect on the membrane structure.