Validity and Reliability of Hindi version of Foot and Ankle Disability Index in patients with chronic recurrent lateral ankle sprain.

BACKGROUND: Lateral Ankle Sprain (LAS) is a recurrent musculoskeletal injury commonly noticed in primary care, podiatry, orthopaedics, and physical therapy centers. The Foot and Ankle Disability Index (FADI) is a self-reported and region-specific tool with no previous literature available on the translation of the FADI scale into Hindi language. AIM: The study aims to translate and evaluate each translated domain of FADI to see its cross-cultural adaptation, content validity and reliability for patients with chronic recurrent LAS. STUDY DESIGN: A Cross-Sectional Study. METHODS: The scale was translated from the reference language to the target language, Hindi, using the instructions provided in the literature. Delphi survey was conducted for content validation followed by recruitment of 51 participants with a history of long lasting repetitive lateral sprain of ankle to evaluate test-retest reliability of Hindi version of FADI. RESULT: The S-CVI/Ave and S-CVI/UA came out to be 0.988 and 0.884, respectively and I-CVI for all items of Hindi version of FADI were more than 0.90. The ICC (Intra-class Correlation Coefficient) and internal consistency was evaluated, which came out to 0.961 and 0.980, respectively for Hindi version of FADI. CONCLUSION: Hindi version of FADI is a valid and reliable scale that has been translated and adapted to be implemented among Indian population suffering from long lasting repetitive LAS.

Effect of Job Rotation Concept for Nursing Staff with Special Reference to Private Based Hospital, Vadodara.

Introduction: Employees are placed in various job rotations between two or more tasks or vocations at regular intervals to ensure that they are exposed to all elements of the company. Job rotation is a methodical approach that permits employees to avoid boredom while also allowing them to develop and grow. Both management and personnel objectives are met with this strategy. It aids in the identification of employee potential and abilities. Through job rotation, employees are exposed to all aspects of the company. Employee abilities and competencies are evaluated ahead of time to ensure that the employee is deployed in the best possible position. However, it does permit the pursuit of personal interests while gaining practical knowledge in a variety of industries or processes. The present study was undertaken with an aim to assess the effect of job rotation on the nursing staff in a private hospital of Vadodara. Methodology: The study was cross-sectional in nature where the perception of the nursing staff was gathered through a structured questionnaire. The questionnaire assessed the perception of the staff on a five point likert scale from strongly agree to strongly disagree. The sample size of the study was 126. Mann Whitney Test and Kruskal Wallis test was used to assess the effect of job rotation with respect to gender and age, years of experience respectively. The statistical analysis was undertaken at 95% confidence level with statistical significance at a p value of less than 0.05. Results: The results depicted that there was no difference in the perception towards effect of job rotation with respect to gender and age group. However, with respect to job rotation not interrupting the employees' work life and no effect on personal life, there was statistical significant difference with respect to the years of experience of the nursing staff as the p value was less than 0.05. Conclusion: Job rotation, in their opinion, causes frequent interruptions in both the job and personal life of those who participate in it. The nurses working in the hospital came up with appropriate job rotation ideas that took into consideration their age and years of experience. It appears that most of the criteria indicate that the nursing staff members were satisfied with their job rotation, which lends support to the findings of the study.

Development and content validation of an ADL questionnaire for hemiplegic shoulder.

Objective: Shoulder problems can be a common secondary musculoskeletal complication after stroke. Common post-stroke shoulder problems include altered muscle tone, pain, and a frozen shoulder. The study was aimed at formulating an activities of daily living (ADL) questionnaire for stroke patients with shoulder problems. Materials and Methods: The study was a cross-sectional content validation study conducted in a tertiary care hospital from August 2020 to March 2021. A literature review and direct patient interview were used to identify items for the scale. Before the construction of the scale, two physiotherapists with relevant field experience were interviewed to identify the items. Then, ten stroke patients were interviewed to generate new items depending on the challenges that they experienced. The scale was subsequently sent to a panel of eight experts for content evaluation. Results: After the first round of Delphi, we excluded the items that failed to achieve at least a 0.8 item-level content validity index (I-CVI). In the first round, 9 items fail to achieve 0.8 I-CVI hence removed from the actual draft of the scale. Total 10 items were included in the second draft and it was sent to the 2nd round of Delphi survey. In this phase, all items got more than 0.8 I-CVI. The average value and universal acceptance of the scale level content validity index have been obtained at 0.96 and 0.8, respectively. It denotes that our proposed questioner got excellent level of content validity. Conclusion: As the ADL questioner got excellent content validity, this scale can be used to assess the ADL functions of hemiplegic shoulder.

Hindi translation, cross-culture adaptation, validation and relaibility of foot and ankle disability index instrument in patients with chronic recurrent lateral ankle sprain-A study protocol.

BACKGROUND: Ankle sprains are one of the most common musculoskeletal injuries. English and Italian versions of the Foot and Ankle Disability Index (FADI) questionnaire are available for assessment, but no Hindi version of the FADI questionnaire is yet available for the population who only communicate and understand the Hindi language. AIM: This study aims to translate and culturally adapt the Hindi version of the FADI questionnaire and to evaluate its validity. STUDY DESIGN: A Cross-Sectional Study. METHOD: In accordance with Beaton guidelines, the FADI questionnaire will be translated into Hindi by two translators with medical and non-medical backgrounds, respectively. The recording observer will then take a seat to create a T1-2 version of the translated questionnaire. A Delphi survey with 6-10 experts will be conducted. The pre-final form will be fully tested on 51 patients, and the scale validity will be reported. Finally, the translated questionnaire version will be analyzed by the ethics committee. RESULT: Statistical analysis will be done using the Scale-level Content Validity Index (S-CVI). An individual item of the questionnaire will be validated and documented in the context of the Item-level Content Validity Index (I-CVI). This will be achieved with the help of the Averaging method (S-CVI/Ave) and the Universal Agreement calculation method (S-CVI/UA). Both absolute and relative reliability will be calculated. For absolute reliability, Bland and Altman agreement will be used. Intra-class correlation coefficient (ICC) and Cronbach's alpha (internal consistency), along with Spearman Rank rho and Pearson product, will be analysed for relative reliability. CONCLUSION: The study will determine the content validity and reliability of the Hindi version of the FADI questionnaire in patients with a chronic recurrent lateral ankle sprain.

Estimulação transcraniana por corrente contínua para melhorar o desempenho matemático em crianças discalculia de desenvolvimento em idade escolar: um único grupo pré-teste-pós-teste, estudo quase experimental / Transcranial direct current stimulation to enhance mathematical performance in school going developmental dyscalculic children: A single group pretest-posttest, quasi experimental study

INTRODUÇÃO: A discalculia do desenvolvimento (DD) lida com o desempenho matemático prejudicado e afeta as atividades educacionais e do dia a dia das crianças. Há evidências de que a estimulação transcraniana por corrente contínua (ETCC) aplicada ao córtex parietal posterior facilita a estrutura neuronal hipoativa e melhora o desempenho matemático em indivíduos com DD. OBJETIVO: O objetivo deste estudo é investigar se tDCS adjuvante com treinamento convencional de numeramento (CNT) aumentaria as habilidades matemáticas de crianças em idade escolar afetadas com DD. MATERIAIS E MÉTODOS: Treze crianças em idade escolar afetadas com DD receberam tDCS e CNT três sessões por semana por até 2 semanas. Foi dada estimulação anódica esquerda e catódica direita na região P3 / P4, com intensidade de 2mA, combinada com CNT por 30 minutos em um dia. O inventário de diagnóstico de deficiência de aprendizagem (LDDI) foi usado como uma medida de resultado e coletado no início e no final da intervenção de 2 semanas. RESULTADOS: Houve melhora significativa no desempenho matemático de crianças em idade escolar. Os resultados mostram uma melhora estatística e clinicamente significativa após 2 semanas de intervenção. CONCLUSÕES: tDCS combinado com CNT é eficaz para melhorar as habilidades matemáticas de crianças em idade escolar afetadas com DD. Os resultados deste estudo fornecem uma nova perspectiva para a reabilitação de crianças com DD em idade escolar.

INTRODUCTION: Developmental dyscalculia (DD) deals with impaired mathematical performance and affects children's educational and day-to-day activities. There is evidence that transcranial direct current stimulation (tDCS) applied to the posterior parietal cortex facilitates the hypoactive neuronal structure and improves mathematical performance in individuals with DD. OBJECTIVE: The objective of this study is to investigate whether tDCS adjuvant with conventional numeracy training (CNT) would enhance the mathematical abilities of school-going children affected with DD. MATERIALS AND METHODS: Thirteen school-going children affected with DD received tDCS and CNT three sessions per week for up to 2 consecutive weeks. Left anodal and right cathodal stimulation at P3/P4 region with 2mA intensity combined with CNT for 30 minutes in a day was given. Learning disability diagnostic inventory (LDDI) was used as an outcome measure and collected at baseline and the end of the 2-week intervention. RESULTS: There was a significant improvement in the mathematical performance of school-going children. The results show statistically as well as a clinically significant improvement after the two weeks of intervention. CONCLUSIONS: tDCS combined with CNT effectively improves the mathematical abilities of school-going children affected with DD. The findings of this study provide a new perspective for the rehabilitation of school-going DD children.

Melanin deposition in two Cryptococcus species depends on cell-wall composition and flexibility.

Cryptococcus neoformans and Cryptococcus gattii are two species complexes in the large fungal genus Cryptococcus and are responsible for potentially lethal disseminated infections. These two complexes share several phenotypic traits, such as production of the protective compound melanin. In C. neoformans, the pigment associates with key cellular constituents that are essential for melanin deposition within the cell wall. Consequently, melanization is modulated by changes in cell-wall composition or ultrastructure. However, whether similar factors influence melanization in C. gattii is unknown. Herein, we used transmission EM, biochemical assays, and solid-state NMR spectroscopy of representative isolates and "leaky melanin" mutant strains from each species complex to examine the compositional and structural factors governing cell-wall pigment deposition in C. neoformans and C. gattii. The principal findings were the following. 1) C. gattii R265 had an exceptionally high chitosan content compared with C. neoformans H99; a rich chitosan composition promoted homogeneous melanin distribution throughout the cell wall but did not increase the propensity of pigment deposition. 2) Strains from both species manifesting the leaky melanin phenotype had reduced chitosan content, which was compensated for by the production of lipids and other nonpolysaccharide constituents that depended on the species or mutation. 3) Changes in the relative rigidity of cell-wall chitin were associated with aberrant pigment retention, implicating cell-wall flexibility as an independent variable in cryptococcal melanin assembly. Overall, our results indicate that cell-wall composition and molecular architecture are critical factors for the anchoring and arrangement of melanin pigments in both C. neoformans and C. gattii species complexes.

The melanization road more traveled by: Precursor substrate effects on melanin synthesis in cell-free and fungal cell systems.

Natural brown-black eumelanin pigments confer structural coloration in animals and potently block ionizing radiation and antifungal drugs. These functions also make them attractive for bioinspired materials design, including coating materials for drug-delivery vehicles, strengthening agents for adhesive hydrogel materials, and free-radical scavengers for soil remediation. Nonetheless, the molecular determinants of the melanin "developmental road traveled" and the resulting architectural features have remained uncertain because of the insoluble, heterogeneous, and amorphous characteristics of these complex polymeric assemblies. Here, we used 2D solid-state NMR, EPR, and dynamic nuclear polarization spectroscopic techniques, assisted in some instances by the use of isotopically enriched precursors, to address several open questions regarding the molecular structures and associated functions of eumelanin. Our findings uncovered: 1) that the identity of the available catecholamine precursor alters the structure of melanin pigments produced either in Cryptococcus neoformans fungal cells or under cell-free conditions; 2) that the identity of the available precursor alters the scaffold organization and membrane lipid content of melanized fungal cells; 3) that the fungal cells are melanized preferentially by an l-DOPA precursor; and 4) that the macromolecular carbon- and nitrogen-based architecture of cell-free and fungal eumelanins includes indole, pyrrole, indolequinone, and open-chain building blocks that develop depending on reaction time. In conclusion, the availability of catecholamine precursors plays an important role in eumelanin development by affecting the efficacy of pigment formation, the melanin molecular structure, and its underlying scaffold in fungal systems.

Efficacy of Osteopathic Manipulative Treatment Approach in the Patient with Pulmonary Fibrosis in Critical Care Outpatient Department.

The purpose of the present case study was to explore the efficacy of osteopathic manipulative treatment (OMT) in patient with pulmonary fibrosis (PF) in the critical care outpatient department. Here, we present a 48-year-old male case with breathlessness, increased frequency of defecation, and pain in and around the nape of neck with diagnosed pulmonary fibrosis. He scored 3 on a patient-reported modified Medical Research Council (mMRC) dyspnea scale. Osteopathic examination reveals multiple somatic findings across the chest and abdominal region and treated by OMT. Pre- and post-intervention changes were assessed by the 13-item shortness of breath with daily activities (13iSOBDA). 27.2, 22, 16.4, and 11.8 were noted at the end of 1st, 2nd, 3rd, and 4th week of intervention, respectively, on 13iSOBDA while mMRC decreased from 3 to 1. OMT may be a feasible option in decreasing the symptoms of the PPF in the critical care outpatient department.

The effectiveness of osteopathic manipulative treatment in an abnormal uterine bleeding related pain and health related quality of life (HR-QoL) - A case report.

Abnormal uterine bleeding is characterized by painful and/or excessive menorrhea, chronic pelvic pain due to the endometriosis (Em). Osteopathic treatment is commonly used in the gynecological dysfunctions. The aim of the present case study was to explore the effect of osteopathic treatment (OT) for a woman with abnormal uterine bleeding related pain and quality of life (QoL). We reported a case of 29 year old female who presented with chief complaints of increased flow during periods, lower abdominal pain, leukorrhoea, lower back pain and with occasional constipation for the last 3 years. Patient is a mother of 6 years old male child born with normal delivery. On diagnostic ultrasonography the uterus was found bulky with insignificant endometriosis and no other abnormality was detected. She did not have any relevant past medical and surgical history. The pre and post osteopathic treatment measurements were measured using Visual Analog Scale (VAS) and the health related quality of life (HR-QoL) questionnaire called short form Endometriosis Health Profile Questionnaire (EHP) - 5. In the present case the pain due to the endometriosis was treated with the osteopathic treatment consists of all the major diaphragms' release (release of pelvic diaphragm, abdominal diaphragm, thoracic outlet release and hyoid diaphragm) during the first session and in the second session gastro-esophageal (GE) junction release, sigmoid colon release, cranial therapy to the occiput, sacral release and dural tube rocking. Following that improvement of pain from VAS 8.3/10 to 3.9/10 and QoL improvement from EHP-5, 72/100 to 26/100 was noted. Osteopathic manipulative approach (OMA) in the patient with Em might improve the abnormal uterine bleeding related pain and health related quality of life (HR-QoL).

The strain - Counter strain technique in the management of anterior interosseous nerve syndrome: A case report.

Anterior interosseous nerve syndrome (AINS) is a proximal median nerve neuropathy affecting the forearm. Trigger points in the anterior compartment of the forearm may cause compression of the anterior interosseous nerve (AIN) which, in turn, may result in muscle weakness. Here we present the case of a 37-year-old female who complained of an abnormal pen grip while writing. Clinical examination (observation, palpation, pincer grip strength) showed weak pincer grip strength, an active trigger point in the middle of the anterior forearm and a positive circle sign. Her treatment course included cryomassage, neural mobilization, transcutaneous electrical nerve stimulation (TENS) and the strain-counter strain (SCS) technique four times a week for two weeks. On follow-up, the patient reported an inactive trigger point on palpation, improvement in her handwriting and improved pincer (fingertip pinch) grip strength in pounds (lbs) as recorded by the Baseline Hydraulic Pinch Gauge. This case report explored the effectiveness of SCS as an important adjunct to other conservative treatments for entrapment neuropathies. SCS has also shown its potential to improve muscle strength.

The California Tri-pull Taping Method in the Treatment of Shoulder Subluxation After Stroke: A Randomized Clinical Trial.

BACKGROUND: Shoulder subluxation is a frequent occurrence in individuals following a stroke. Although various methods of treatment are available, none of them address all possible consequences of the subluxation pain, limited range of motion, the subluxation, and decreased functional use of the arm. AIMS: The purpose of this study was to evaluate the effectiveness of California tri-pull taping (CTPT) method on shoulder subluxation, pain, active shoulder flexion, and upper limb functional recovery after stroke. MATERIALS AND METHODS: This was a randomized control study on 30 participants. All participants received conventional neurorehabilitation 5 days a week over 6 weeks. Half of the participants also received the CTPT. Pre- and post-assessment scores were taken on all participants for the amount of shoulder subluxation, pain, active shoulder flexion, and functional recovery. RESULTS: The CTPT method demonstrated a significant reduction of pain in the treatment group from baseline, a significant improvement in active shoulder flexion and a significant improvement in proximal arm function as measured on the proximal subscale on the Fugl-Meyer upper extremity functional Scale but not the distal or total Fugl-Meyer subscales. Shoulder subluxation was not statistically significant. CONCLUSIONS: The CTPT method is an effective treatment for the hemiplegic subluxed shoulder.

Solid-State (13)C NMR Delineates the Architectural Design of Biopolymers in Native and Genetically Altered Tomato Fruit Cuticles.

Plant cuticles on outer fruit and leaf surfaces are natural macromolecular composites of waxes and polyesters that ensure mechanical integrity and mitigate environmental challenges. They also provide renewable raw materials for cosmetics, packaging, and coatings. To delineate the structural framework and flexibility underlying the versatile functions of cutin biopolymers associated with polysaccharide-rich cell-wall matrices, solid-state NMR spectra and spin relaxation times were measured in a tomato fruit model system, including different developmental stages and surface phenotypes. The hydrophilic-hydrophobic balance of the cutin ensures compatibility with the underlying polysaccharide cell walls; the hydroxy fatty acid structures of outer epidermal cutin also support deposition of hydrophobic waxes and aromatic moieties while promoting the formation of cell-wall cross-links that rigidify and strengthen the cuticle composite during fruit development. Fruit cutin-deficient tomato mutants with compromised microbial resistance exhibit less efficient local and collective biopolymer motions, stiffening their cuticular surfaces and increasing their susceptibility to fracture.

Activation of Melanin Synthesis in Alternaria infectoria by Antifungal Drugs.

The importance of Alternaria species fungi to human health ranges from their role as etiological agents of serious infections with poor prognoses in immunosuppressed individuals to their association with respiratory allergic diseases. The present work focuses on Alternaria infectoria, which was used as a model organism of the genus, and was designed to unravel melanin production in response to antifungals. After we characterized the pigment produced by A. infectoria, we studied the dynamics of 1,8-dihydroxynaphthalene (DHN)-melanin production during growth, the degree of melanization in response to antifungals, and how melanization affected susceptibility to several classes of therapeutic drugs. We demonstrate that A. infectoria increased melanin deposition in cell walls in response to nikkomycin Z, caspofungin, and itraconazole but not in response to fluconazole or amphotericin B. These results indicate that A. infectoria activates DHN-melanin synthesis in response to certain antifungal drugs, possibly as a protective mechanism against these drugs. Inhibition of DHN-melanin synthesis by pyroquilon resulted in a lower minimum effective concentration (MEC) of caspofungin and enhanced morphological changes (increased hyphal balloon size), characterized by thinner and less organized A. infectoria cell walls. In summary, A. infectoria synthesizes melanin in response to certain antifungal drugs, and its susceptibility is influenced by melanization, suggesting the therapeutic potential of drug combinations that affect melanin synthesis.

Structural Characterization of Melanin Pigments from Commercial Preparations of the Edible Mushroom Auricularia auricula.

Many of the most widely consumed edible mushrooms are pigmented, and these have been associated with some beneficial health effects. Nevertheless, the majority of the reported compounds associated with these desirable properties are non-pigmented. We have previously reported that melanin pigment from the edible mushroom Auricularia auricula can protect mice against ionizing radiation, although no physicochemical characterization was reported. Consequently, in this study we have characterized commercial A. auricula mushroom preparations for melanin content and carried out structural characterization of isolated insoluble melanin materials using a panel of sophisticated spectroscopic and physical/imaging techniques. Our results show that approximately 10% of the dry mass of A. auricula is melanin and that the pigment has physicochemical properties consistent with those of eumelanins, including hosting a stable free radical population. Electron microscopy studies show that melanin is associated with the mushroom cell wall in a manner similar to that of melanin from the model fungus C. neoformans. Elemental analysis of melanin indicated C, H, and N ratios consistent with 5,6-dihydroxyindole-2-carboxylic acid/5,6-dihydroxyindole and 1,8-dihydroxynaphthalene eumelanin. Validation of the identity of the isolated product as melanin was achieved by EPR analysis. A. auricula melanin manifested structural differences, relative to the C. neoformans melanin, with regard to the variable proportions of alkyl chains or oxygenated carbons. Given the necessity for new oral and inexpensive radioprotective materials coupled with the commercial availability of A. auricula mushrooms, this product may represent an excellent source of edible melanin.

Solid-state NMR Reveals the Carbon-based Molecular Architecture of Cryptococcus neoformans Fungal Eumelanins in the Cell Wall.

Melanin pigments protect against both ionizing radiation and free radicals and have potential soil remediation capabilities. Eumelanins produced by pathogenic Cryptococcus neoformans fungi are virulence factors that render the fungal cells resistant to host defenses and certain antifungal drugs. Because of their insoluble and amorphous characteristics, neither the pigment bonding framework nor the cellular interactions underlying melanization of C. neoformans have yielded to comprehensive molecular-scale investigation. This study used the C. neoformans requirement of exogenous obligatory catecholamine precursors for melanization to produce isotopically enriched pigment "ghosts" and applied 2D (13)C-(13)C correlation solid-state NMR to reveal the carbon-based architecture of intact natural eumelanin assemblies in fungal cells. We demonstrated that the aliphatic moieties of solid C. neoformans melanin ghosts include cell-wall components derived from polysaccharides and/or chitin that are associated proximally with lipid membrane constituents. Prior to development of the mature aromatic fungal pigment, these aliphatic moieties form a chemically resistant framework that could serve as the scaffold for melanin synthesis. The indole-based core aromatic moieties show interconnections that are consistent with proposed melanin structures consisting of stacked planar assemblies, which are associated spatially with the aliphatic scaffold. The pyrrole aromatic carbons of the pigments bind covalently to the aliphatic framework via glycoside or glyceride functional groups. These findings establish that the structure of the pigment assembly changes with time and provide the first biophysical information on the mechanism by which melanin is assembled in the fungal cell wall, offering vital insights that can advance the design of bioinspired conductive nanomaterials and novel therapeutics.

Demonstration of a common indole-based aromatic core in natural and synthetic eumelanins by solid-state NMR.

Despite the essential functions of melanin pigments in diverse organisms and their roles in inspiring designed nanomaterials for electron transport and drug delivery, the structural frameworks of the natural materials and their biomimetic analogs remain poorly understood. To overcome the investigative challenges posed by these insoluble heterogeneous pigments, we have used l-tyrosine or dopamine enriched with stable (13)C and (15)N isotopes to label eumelanins metabolically in cell-free and Cryptococcus neoformans cell systems and to define their molecular structures and supramolecular architectures. Using high-field two-dimensional solid-state nuclear magnetic resonance (NMR), our study directly evaluates the assumption of structural commonality between synthetic melanin models and the corresponding natural pigments, demonstrating a common indole-based aromatic core in the products from contrasting synthetic protocols for the first time.

Deconstructing a plant macromolecular assembly: chemical architecture, molecular flexibility, and mechanical performance of natural and engineered potato suberins.

Periderms present in plant barks are essential protective barriers to water diffusion, mechanical breakdown, and pathogenic invasion. They consist of densely packed layers of dead cells with cell walls that are embedded with suberin. Understanding the interplay of molecular structure, dynamics, and biomechanics in these cell wall-associated insoluble amorphous polymeric assemblies presents substantial investigative challenges. We report solid-state NMR coordinated with FT-IR and tensile strength measurements for periderms from native and wound-healing potatoes and from potatoes with genetically modified suberins. The analyses include the intact suberin aromatic-aliphatic polymer and cell-wall polysaccharides, previously reported soluble depolymerized transmethylation products, and undegraded residues including suberan. Wound-healing suberized potato cell walls, which are 2 orders of magnitude more permeable to water than native periderms, display a strikingly enhanced hydrophilic-hydrophobic balance, a degradation-resistant aromatic domain, and flexibility suggestive of an altered supramolecular organization in the periderm. Suppression of ferulate ester formation in suberin and associated wax remodels the periderm with more flexible aliphatic chains and abundant aromatic constituents that can resist transesterification, attenuates cooperative hydroxyfatty acid motions, and produces a mechanically compromised and highly water-permeable periderm.

Tomato Cutin Deficient 1 (CD1) and putative orthologs comprise an ancient family of cutin synthase-like (CUS) proteins that are conserved among land plants.

The aerial epidermis of all land plants is covered with a hydrophobic cuticle that provides essential protection from desiccation, and so its evolution is believed to have been prerequisite for terrestrial colonization. A major structural component of apparently all plant cuticles is cutin, a polyester of hydroxy fatty acids; however, despite its ubiquity, the details of cutin polymeric structure and the mechanisms of its formation and remodeling are not well understood. We recently reported that cutin polymerization in tomato (Solanum lycopersicum) fruit occurs via transesterification of hydroxyacylglycerol precursors, catalyzed by the GDSL-motif lipase/hydrolase family protein (GDSL) Cutin Deficient 1 (CD1). Here, we present additional biochemical characterization of CD1 and putative orthologs from Arabidopsis thaliana and the moss Physcomitrella patens, which represent a distinct clade of cutin synthases within the large GDSL superfamily. We demonstrate that members of this ancient and conserved family of cutin synthase-like (CUS) proteins act as polyester synthases with negligible hydrolytic activity. Moreover, solution-state NMR analysis indicates that CD1 catalyzes the formation of primarily linear cutin oligomeric products in vitro. These results reveal a conserved mechanism of cutin polyester synthesis in land plants, and suggest that elaborations of the linear polymer, such as branching or cross-linking, may require additional, as yet unknown, factors.