Importance of amino-terminus in maintenance of oligomeric structure of cytosolic serine hydroxymethyltransferase

The role of the amino and carboxyl-terminal regions of cytosolic serine hydroxymethyltransferase (SHMT) in subunit assembly and catalysis was studied using six amino-terminal (lacking the first 6, 14, 30, 49, 58, and 75 residues) and two carboxyl-terminal (lacking the last 49 and 185 residues) deletion mutants. These mutants were constructed from a full length cDNA clone using restriction enzyme/PCR-based methods and overexpressed in Escherichia coli. The overexpressed proteins, des-(A1-K6)-SHMT and des-(A1- W14)-SHMT were present in the soluble fraction and they were purified to homogeneity. The deletion clones, for des-(A1–V30)-SHMT and des-(A1–L49)-SHMT were expressed at very low levels, whereas des-(A1–R58)-SHMT, des-(A1–G75)-SHMT, des-(Q435–F483)-SHMT and des-(L299-F483)-SHMT mutant proteins were not soluble and formed inclusion bodies. Des-(A1–K6)-SHMT and des-(A1–W14)-SHMT catalyzed both the tetrahydrofolate-dependent and tetrahydrofolate-independent reactions, generating characteristic spectral intermediates with glycine and tetrahydrofolate. The two mutants had similar kinetic parameters to that of the recombinant SHMT (rSHMT). However, at 55 °C, the des-(A1–W14)-SHMT lost almost all the activity within 5 min, while at the same temperature rSHMT and des-(A1–K6)-SHMT retained 85% and 70% activity, respectively. Thermal denaturation studies showed that des-(A1–W14)-SHMT had a lower apparent melting temperature (52°C) compared to rSHMT (56°C) and des-(A1–K6)-SHMT (55 °C), suggesting that N-terminal deletion had resulted in a decrease in the thermal stability of the enzyme. Further, urea induced inactivation of the enzymes revealed that 50% inactivation occurred at a lower urea concentration (1.2 ± 0.1 M) in the case of des-(A1–W14)-SHMT compared to rSHMT (1.8 ±0.1 M) and des-(A1–K6)-SHMT (1.7 ±0.1 M). The apoenzyme of des-(A1- W14)-SHMT was present predominantly in the dimer form, whereas the apoenzymes of rSHMT and des-(A1–K6)-SHMT were a mixture of tetramers (≈75% and ≈65%, respectively) and dimers. While, rSHMT and des-(A1–K6)-SHMT apoenzymes could be reconstituted upon the addition of pyridoxal-5'-phosphate to 96% and 94% enzyme activity, respectively, des-(A1–W14)-SHMT apoenzyme could be reconstituted only upto 22%. The percentage activity regained correlated with the appearance of visible CD at 425 nm and with the amount of enzyme present in the tetrameric form upon reconstitution as monitored by gel filtration. These results demonstrate that, in addition to the cofactor, the N-terminal arm plays an important role in stabilizing the tetrameric structure of SHMT.

Importance of the amino terminus in maintenance of oligomeric structure of sheep liver cytosolic serine hydroxymethyltransferase

The Role Of The Amino And Carboxyl-Terminal Regions Of Cytosolic Serine Hydroxymethyltransferase (SHMT) In Subunit Assembly And Catalysis Was Studied Using Sis Amino-Terminal (Lacking The First 6, 14, 30, 49, 58, And 75 Residues) And Two Carboxyl-Terminal (Lacking The Last 49 And 185 Residues) Deletion Mutants. These Mutants Were Constructed From A Full Length Cdna Clone Using Restriction Enzyme/PCR-Based Methods And Overexpressed In Escherichia Coli. The Overexpressed Proteins, Des-(A1-K6) SHMT And Des-(A1-W14)-SHMT Were Present In The Soluble Fraction And They Were Purified To Homogeneity. The Deletion Clones, For Des-(A1-V30)-SHMT And Des-(A1-L49)-SHMT Were Expressed At Very Low Levels, Whereas Des-(A1-R58)-SHMT, Des-/A1-G75)-SHMT, Des-(Q435-F483)-SHMT And Des-(L299-F483)-SHMT Mutant Proteins Were Not Soluble And Formed Inclusion Bodies. Des-(A1-K6)-SHMT And Des-(A1-W14)-SHMT Catalyzed Both The Tetrahydrofolate-Dependent And Tetrahydrofolate-Independent Reactions, Generating Characteristic Spectral Intermediates With Glycine And Tetrahydrofolate. The Two Mutants Had Similar Kinetic Parameters To That Of The Recombinant SHMT (Rshmt). However, At 55 Degrees C, The Des-(A1-W14)-SHMT Lost Almost All The Activity Within 5 Min, While At The Same Temperature Rshmt And Des-(A1-K6)-SHMT Retained 85% And 70% Activity, Respectively. Thermal Denaturation Studies Showed That Des-(A1-W14)-SHMT Had A Lower Apparent Melting Temperature (52 Degrees C) Compared To Rshmt (56 Degrees C) And Des-(A1-K6)-SHMT (55 Degrees C), Suggesting That N-Terminal Deletion Had Resulted In A Decrease In The Thermal Stability Of The Enzyme. Further Urea Induced Inactivation Of The Enzymes Revealed That 50% Inactivation Occurred At A Lower Urea Concentration (1.2+/-0.1 M) In The Case Of Des-(A1-W14)-SHMT Compared To Rshmt (1.8+/-0.1 M) And Des-(A1 -K6)-SHMT (1.7+/-0.1 M). The Apoenzyme Of Des-/A1-K6)-SHMT Was Present Predominantly In The Dimer Form, Whereas The Apoenzymes Of Rshmt And Des-(A1-K6)-SHMT Were A Mixture Of Tetramers (Approximate To 75% And Approximate To 65%, Respectively) And Dimers. While, Rshmt And Des-(A1-K6)-SHMT Apoenzymes Could Be Reconstituted Upon The Addition Of Pyridoxal-5'-Phosphate To 96% And 94% Enzyme Activity, Respectively Des-(A1-W14)-SHMT Apoenzyme Could Be Reconstituted Only Upto 22%. The Percentage Activity Refined Correlated With The Appearance Of Visible CD At 425 Nm And With The Amount Of Enzyme Present In The Tetrameric Form Upon Reconstitution As Monitored By Gel Filtration. These Results Demonstrate That, In Addition To The Cofactor, The N-Terminal Arm Plays An Important Role In Stabilizing The Tetrameric Structure Of SHMT.

CSSP (Consensus Secondary Structure Prediction): a web-based server for structural biologists

Sequence-structure correlation studies are important in deciphering the relationships between various structural aspects, which may shed light on the protein-folding problem. The first step of this process is the prediction of secondary structure for a protein sequence of unknown three-dimensional structure. To this end, a web server has been created to predict the consensus secondary structure using well known algorithms from the literature. Furthermore, the server allows users to see the occurrence of predicted secondary structural elements in other structure and sequence databases and to visualize predicted helices as a helical wheel plot. The web server is accessible at http://bioserver1.physics.iisc.ernet.in/cssp/.

trans-Dichloro-bis-(arylazoimidazole)palladium(II): Synthesis, Structure, Photoisomerization, and DFT Calculation

Reaction between PdCl2 and 1-alkyl-2-(arylazo)imidazole (RaaiR') or 1-alkyl-2-(naphthyl-alpha/beta-azo)imidazole (alpha/beta-NaiR') under reflux in ethanol has isolated complexes of compositions Pd(RaaiR')(2)Cl-2 (5, 6) and Pd(alpha/beta-NaiR')(2)Cl-2 (7, 8). The X-ray structure determination of one of the molecules, Pd(alpha-NaiBz)(2)Cl-2 (7c), has reported a trans-PdCl2 configuration, and alpha-NaiBz acts as monodentate N(imidazole) donor ligand. The spectral (IR, UV-vis, H-1 NMR) data support the structure. UV light irradiation (light source: Perkin-Elmer LS 55 spectrofluorimeter, Xenon discharge lamp, lambda = 360-396 nm) in a MeCN solution of the complexes shows E-to-Z isomerization of the coordinated azoimidazole unit. The reverse transformation, Z-to-E, is very slow with visible light irradiation. Quantum yields (phi(E-Z)) of E-to-Z isomerization are calculated, and phi is lower than that of the free ligand but comparable with those of Cd(II) and Hg(II) complexes of the same ligand. The Z-to-E isomerization is a thermally induced process. The activation energy (E-a) of Z-to-E isomerization is calculated by controlled-temperature experimentation. cis-Pd(azoimidazole)Cl-2 complexes (azomidazole acts as N(imidazole) and N(azo) Chelating ligand) do not respond upon light irradiation, which supports the idea that the presence of noncoordinated azo-N to make free azo (-N=N-) function is important to reveal photochromic activity. DFT calculation of Pd(alpha-NaiBz)(2)Cl-2 (7c) has suggested that the HOMO of the molecule is constituted of Pd (32%) and Cl (66%), and hence photo excitation may use the energy of Pd and Cl instead of that of the photofunctional -N=N-Ar motif; thus, the rate of photoisomerization and quantum yield decrease versus the free ligand values.

Stress analysis on human arterial plaques by fluid structure interactions - Multi-case study

Atherosclerotic plaque rupture has been extensively considered as the leading cause of death in the world. It is believed that high stress within plaque can be an important factor which can trigger the rupture of the plaque. High resolution multi-spectral magnetic resonance imaging (MRI) has allowed the plaque components (arterial wall, lipids, and fibrous cap) to be visualized in vivo [1]. The patient specific finite element model can be generated from the image data to perform stress analysis and provide critical information on understanding plaque rupture mechanisms [2]. The present work is to apply the procedure to a total of 14 patients (S1 ∼ S14), to study the stress distributions on carotid artery plaque reconstructed from multi-spectral magnetic resonance images, and the possible relationships between stress and plaque burdens.

The Phraseology and Structure of Latin Building Inscriptions in Roman North Africa

This study analyses the diction of Latin building inscriptions. Despite its importance, this topic has rarely been discussed before: the most substantial contribution on the subject is a short dissertation by Klaus Gast (1965) that focuses on 100 inscriptions dating mostly from the Republican period. Marietta Horster (2001) also touched upon this theme in her thesis on imperial building inscriptions. I have collected my source material in North Africa because more Latin building inscriptions dating from the Imperial period have survived there than in any other area of the Roman Empire. By means of a thorough and independent survey, I have assembled all relevant African Latin building inscriptions datable to the Roman period (between 146 BC and AD 425), 1002 texts, into a corpus. These inscriptions are all fully edited in Appendix 1; Appendix 2 contains references to earlier editions. To facilitate search operations, both are also available in electronic form. They are downloadable from the address http://www.helsinki.fi/hum/kla/htm/jatkoopinnot.htm. Chapter one is an introduction dealing with the nature of building inscriptions as source material. Chapter two offers a statistical overview of the material. The following main section of the work falls into five chapters, each of which analyses one main part of a building inscription. An average building inscription can be divided into five parts: the starting phrase opens the inscription (a dedication to gods, for example), the subject part identifies the builder, the object part describes the constructed or repaired building, the predicate part records the building activity and the supplement part offers additional information on the project (it can specify the funding, for instance). These chapters are systematic and chronological and their purpose is to register and interpret the phrases used, to analyse reasons for their use and for their popularity among the different groups of builders. Chapter eight, which follows the main section of the work, creates a typology of building inscriptions based on their structure. It also presents the most frequently attested types of building inscriptions. The conclusion describes, on a general level, how the diction of building inscriptions developed during the period of study and how this striking development resulted from socio-economic changes that took place in Romano-African society during Antiquity. This study shows that the phraseology of building inscriptions had a clear correlation both with the type of builder and with the date of carving. Private builders tended to accentuate their participation (especially its financial side) in the project; honouring the emperor received more emphasis in the building inscriptions set up by communities; the texts produced by the army were concise. The chronological development is so clear that it enables stylistic dating. At the beginning of the imperial period the phrases were clear, concrete, formal and stereotyped but by Late Antiquity they have become vague, subjective, flexible, varied and even rhetorically or poetically coloured.

Stock-recruitment relationships of the tiger prawns (Penaeus esculentus and Penaeus semisulcatus) in the Australian Northern Prawn Fishery

This paper investigates the stock-recruitment and equilibrium yield dynamics for the two species of tiger prawns (Penaeus esculentus and Penaeus semisulcatus) in Australia's most productive prawn fishery: the Northern Prawn Fishery. Commercial trawl logbooks for 1970-93 and research surveys are used to develop population models for these prawns. A population model that incorporates continuous recruitment is developed. Annual spawning stock and recruitment indices are then estimated from the population model. Spawning stock indices represent the abundance of female prawns that are likely to spawn; recruitment indices represent the abundance of all prawns less than a certain size. The relationships between spawning stock and subsequent recruitment (SRR), between recruitment and subsequent spawning stock (RSR), and between recruitment and commercial catch were estimated through maximum-likelihood models that incorporated autoregressive terms. Yield as a function of fishing effort was estimated by constraining to equilibrium the SRR and RSR. The resulting production model was then used to determine maximum sustainable yield (MSY) and its corresponding fishing effort (f(MSY)). Long-term yield estimates for the two tiger prawn species range between 3700 and 5300 t. The fishing effort at present is close to the level that should produce MSY for both species of tiger prawns. However, current landings, recruitment and spawning stock are below the equilibrium values predicted by the models. This may be because of uncertainty in the spawning stock-recruitment relationships, a change in carrying capacity, biased estimates of fishing effort, unreliable catch statistics, or simplistic assumptions about stock structure. Although our predictions of tiger prawn yields are uncertain, management will soon have to consider new measures to counteract the effects of future increases in fishing effort.

Structure and ultrastructure of the silk glands and spinneret of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae)

This study provides comprehensive documentation of silk production in the pest moth Helicoverpa armigera from gland secretion to extrusion of silk thread. The structure of the silk glands, accessory structures and extrusion apparatus are reported. The general schema of the paired silk glands follows that found for Lepidoptera. Morphology of the duct, silk press, muscle attachments and spigot are presented as a three-dimensional reconstruction and the cuticular crescent-shaped profile of the silk press is demonstrated in both open and closed forms with attendant muscle blocks, allowing advances in our knowledge of how the silk press functions to regulate the extrusion of silk. Growth of the spigot across instars is documented showing a distinctive developmental pattern for this extrusion device. Its shape and structure are related to use and load-bearing activity.

Photo-induced double-strand DNA and site-specific protein cleavage activity of L-histidine (mu-oxo)diiron(III) complexes of heterocyclic bases

Three oxo-bridged diiron(III) complexes of L-histidine and heterocyclic bases [Fe-2(mu-O)(L-his)(2)(B)(2)](ClO4)(2) (1-3), where B is 2,2'-bipyridine (bpy),1,10-phenanthroline (phen), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq), were prepared and characterized. The bpy complex 1 was structurally characterized by X-ray crystallography. The molecular structure showed a {Fe-2(mu-O)} core in which iron(III) in a FeN4O2 coordination is bound to tridentate monoanionic L-histidine and bidentate bpy ligands. The Fe center dot center dot center dot Fe distance is similar to 3.5 angstrom. The Fe-O-Fe unit is essentially linear, giving a bond angle of similar to 172 degrees. The complexes showed irreversible cyclic voltammetric cathodic response near -0.1 V vs. SCE in H2O-0.1 M KCl. The binuclear units displayed antiferromagnetic interaction between two high-spin (S = 5/2) iron(III) centers giving a -J value of -110 cm(-1). The complexes showed good DNA binding propensity giving a binding constant value of similar to 10(5) M-1. Isothermal titration calorimetric data indicated single binding mode to the DNA. The binding was found to be driven by negative free energy change and enthalpy. The dpq complex 3 showed oxidative double-strand DNA cleavage on exposure to UV-A and visible light. The phen complex 2 displayed single-strand photocleavage of DNA. The DNA double-strand breaks were rationalized from theoretical molecular docking calculations. Mechanistic investigations showed formation of hydroxyl radicals as the reactive species through photodecarboxylation of the L-histidine ligand. The complexes exhibited good binding propensity to bovine serum albumin (BSA) protein in Tris-HCl/NaCl buffer medium. The dpq complex 3 showed UV-A light-induced site-specific oxidative BSA cleavage forming fragments of similar to 45 kDa and similar to 20 kDa molecular weights via SOH pathway.

Post-industrial Intervention : An Activity-Theoretical Expedition Tracing the Proximal Development of Forms of Conducting Interventions

Ei saatavilla

Synthesis, characterization and photocatalytic activity of MxCe1-xVO4 (M = Li, Ca and Fe)

Non-stoichiometric substituted cerium vanadates, MxCe1-xVO4 (M = Li, Ca and Fe), were synthesized by solid-state reactions. The crystal structure was analyzed by powder X-ray diffraction and it exhibits a tetragonal zircon Structure, crystallizing in the space group I4(1)/amd with a = 7.3733(4) and c = 6.4909(4) angstrom and Z = 4. Particle sizes were in the range of 600-800 nm, as observed by scanning electron microscopy. The thermal analysis of the compounds showed phase stability up to 1100 degrees C. The UV diffuse reflectance spectra indicated that the compounds have band gaps in the range of 2.6-2.9 eV. The photocatalytic activity of these Compounds was investigated for the first time for the degradation of different dyes, and organics, the oxidation of cyclohexane and the hydroxylation of benzene. The degradation of dyes was modeled using the Langmuir-Hinshelwood kinetics, while the oxidation of cyclohexane and hydroxylation of benzene were modeled using a free radical mechanism and a series reaction mechanism, respectively.

Evidence of episodic brittle faulting in the cratonic part of the Peninsular India and its implications for seismic hazard in slow deforming regions

The region around Waclakkancheri, in the province of Kerala, India, which lies in the vicinity of Palghat-Cauvery ;hear zone (within the Precambrian crystalline terrain), has been a site of microseismic activity since 1989. Earlier studies had identified a prominent WNW-ESE structure overprinting on the E-W trending lineaments associated with Palghat-Cauvery shear zone. We have mapped this structure, located in a chamockite quarry near Desamangalam, Waclakkancheri, which we identify as a ca. 30 km-long south dipping reverse fault. This article presents the characteristics of this fault zone exposed on the exhumed crystalline basement and discusses its significance in understanding the earthquake potential of the region. This brittle deformation zone consists of fracture sets with small-scale displacement and slip planes with embedded fault gouges. The macroscopic as well as the microscopic studies of this fault zone indicate that it evolved through different episodes of faulting in the presence of fluids. The distinct zones within consolidated gouge and the cross cutting relationship of fractures indicate episodic fault activity. At least four faulting episodes can be recognized based on the sequential development of different structural elements in the fault rocks. The repeated ruptures are evident along this shear zone and the cyclic behavior of this fault consists of co-seismic ruptures alternating with inter-seismic periods, which is characterized by the sealed fractures and consolidated gouge. The fault zone shows a minimum accumulated dip/oblique slip of 2.1 m in the reverse direction with a possible characteristic slip of 52 cm (for each event). The ESR dating of fault gouge indicates that the deformation zone records a major event in the Middle Quaternary. The empirical relationships between fault length and slip show that this fault may generate events M >= 6. The above factors suggest that this fault may be characterized as potentially active. Our study offers some new pointers that can be used in other slow deforming cratonic hinterlands in exploring the discrete active faults.

Stock structure of exploited shark species in north-eastern Australia

The project has provided management and other stakeholders with information necessary to make informed decisions about the management of four of the key exploited shark species caught in the Queensland inshore net fishery and northern New South Wales line fishery. The project has determined that spatial management of milk sharks within Queensland, and scalloped hammerhead, common black tip and Australian black tip sharks within Queensland and New South Wales is appropriate. The project has determined that both black tip shark species are likely to require co-operative management arrangements between Queensland and New South Wales. For scalloped hammerheads separate stocks between the two jurisdictions were identified from the fisheriesdependent samples, however genetic exchange across borders is likely to be facilitated by movement of adult females and perhaps larger males to a lesser extent. This information will greatly assist compliance with the Commonwealth Environment Protection and Biodiversity Conservation Act (1999) for shark fisheries in north-eastern Australia by providing the necessary basis for robust assessment of the status of stocks of the study species, thereby helping to deliver their sustainable harvest. It also helps to achieve objectives of the Australian National Shark Plan. The project provides the appropriate spatial framework for future monitoring and assessment of the study species. This is at a time when shark fisheries are receiving close attention from all sectors and when monitoring programs are being implemented, aimed at better assessment of stock status. This project has provided the crucial information for developing an appropriate monitoring design as well as the necessary basis for making statements about stock status. The project has addressed research priorities identified by the Queensland Fisheries Research Advisory Board, Great Barrier Reef Marine Park Authority and Queensland Fisheries. Previously management has assumed a single stock for each species on the east coast of Queensland, and management of shark fisheries in New South Wales (NSW) and Queensland has been independent of one another. The project has been able to enhance and develop links between research, management and industry. Strong positive relationships with commercial fishers were crucial in the collection of samples throughout the study area and fisheries managers were part of the project team throughout the study period. During the project the study area was extended to include both Queensland and NSW waters, creating mutualistic and positive links between the States’ research and management agencies. Extension of project results included management representatives from NSW and Queensland, as well as the Northern Territory where similar shark fisheries operate and similar species are targeted. The project was able to provide significant human capital development opportunities providing considerable value to the project outcomes. Use of vertebral microchemistry and life history characteristics as stock determination methods provided material for two PhD students based at James Cook University: Ron Schroeder, vertebral chemistry; and Alastair Harry, life history characteristic. The project has developed novel research methods that have great capacity for future application, including: • Development of a simple and rapid genetic diagnostic tool (RT-HRM-PCR assay) for differentiating among the black tip shark species, for which no simple morphological identifier exists; and • Development of laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) methods for analysing and interpreting microchemical composition of shark vertebrae. The study has provided further confirmation of the effectiveness of using a holistic approach in stock structure studies and justifies investment into such studies.

Possible involvement of a calcium-stimulated ATP-hydrolyzing activity associated with mycobacteriophage I3 in the DNA injection process.

Ca2+ ions are necessary for the successful propagation of mycobacteriophage I3. An assay for the phage DNA release in the presence of an isolated cell wall preparation from the host was established, and in this system Ca2+ ions also stimulated the release of DNA. The inhibition of phage DNA injection caused by Tween 80 (polyoxyethylene sorbitan monooleate), a nonionic detergent routinely used in mycobacterial cultures, was reversed by Ca2+. The presence of a phage-associated ATP-hydrolyzing activity was demonstrated. This enzyme was stimulated by Ca2+ ions and inhibited by Tween 80. From this and the behavior of the two agents at the level of DNA injection, as well as the fact that phage I3 has a contractile tail structure, we conclude that the phage-associated ATPase is involved in the DNA injection process.

Study of the structure and function of the sheath of tropically adapted bulls and risk factors for preputial eversion and preputial prolapse

Preputial prolapse is an obvious condition affecting bulls from many breeds. Unfortunately, the losses in production and welfare concerns associated with preputial prolapse can remain undetected for long periods of time in the extensive beef areas of northern Australia where the bulls are not inspected regularly. Thus, there is a critical need to identify the structural factors predisposing to preputial prolapse in young bulls so that they can be culled early. Despite there being no firm scientific evidence of an association between preputial eversion and preputial prolapse, it seems logical that the increased exposure of the sensitive prepuce as a consequence of preputial eversion may increase the risk of bulls developing preputial pathology, in particular preputial prolapse. This may be particularly relevant in Bos indicus bulls as they have a more pendulous sheath and thus eversion of the prepuce may be associated with a greater risk of injury to the prepuce compared to that in Bos taurus bulls. Further, studies of preputial eversion in Bos taurus bulls have concluded that there is an association between polledness and increased prevalence and severity (length of everted prepuce and duration of eversion) of preputial eversion due primarily to the absence or poor development of the caudal preputial muscles. No similar definitive work in Bos indicus bulls has been conducted and thus anatomical studies reported in this thesis were conducted to determine if a similar association occurred in Bos indicus bulls. A survey of a sample of large beef breeding herds in northern Australia found that preputial prolapse is a significant problem in Bos indicus and Bos indicus derived bulls and affected both young and older bulls. The importance of preputial prolapse confirmed the value of further research into the causes of this problem. A series of anatomical studies confirmed that preputial eversion in Bos indicus derived bulls was not more prevalent in polled bulls than horned bulls and was not associated with deficiency of the caudal preputial muscles as was established in Bos taurus bulls. An anatomical study of Bos indicus derived bulls with preputial prolapse found that preputial prolapse occurred in horned bulls of varying ages and these bulls did not have any evidence of deficiency in the caudal preputial muscles. However, preputial prolapse was observed in young polled bulls that had poorly developed or absent caudal preputial muscles. It was concluded that deficiency of the caudal preputial muscles in polled Bos indicus derived bulls may predispose to preputial prolapse at an early age, but no predisposing anatomical factors were found for horned Bos indicus derived bulls. In these studies, preputial eversion and preputial prolapse were found in horned Bos indicus derived bulls that did not have any preputial muscle deficiency and it was noted that preputial eversion was not related to the length of the prepuce. Further studies confirmed that preputial eversion was linearly and consistently associated with position of the glans penis within the sheath in Bos indicus derived bulls, and movement of the glans penis towards the preputial orifice consistently resulted in preputial eversion in these bulls. A method to objectively measure the relationship between movement of the glans penis within the sheath and preputial eversion was developed. Studies in humans have linked function of some abdominal muscles to function of the pelvic organs. This relationship was investigated in Bos indicus derived bulls to determine whether the function of specific abdominal muscles affected position of the penis in the sheath. Using the method developed to objectively measure the relationship between penis movement and preputial eversion, the abdominal muscles that potentially were associated with movement of the glans penis or preputial eversion were examined but no significant relationships were observed. In the anatomical study of Bos indicus derived bulls not affected with preputial prolapse a more pendulous sheath was associated with increased prevalence of preputial eversion. This relationship was confirmed for horned and polled bulls in the penis movement studies. Bos indicus derived bulls with more pendulous sheaths evert their prepuces more than bulls with less pendulous sheaths thus increasing the risk of damage to the prepuce either from the environment, other bulls, or from them inadvertently stepping on the everted prepuce when they get to their feet. Culling Bos indicus derived bulls with more pendulous sheaths should reduce the incidence of preputial eversion and possibly preputial prolapse. The anatomical study of Bos indicus derived bulls that did not have preputial prolapse demonstrates that there are herds of bulls where the polled bulls do not have any evidence of deficiency of the caudal preputial iv muscles. There is a need to develop a practical and cost effective test to identify polled Bos indicus bulls that have a deficiency in their caudal preputial muscles.