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1.
Int Wound J ; 16(4): 1013-1023, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31148413

RESUMO

Bacterial collagenase from the aerobic non-pathogenic Vibrio alginolyticus chemovar iophagus is an extracellular metalloproteinase. This collagenase preparation is obtained through a fermentation process and is purified chromatographically, resulting in a highly purified 82-kDa single-band protein that does not contain non-specific proteases or other microbial impurities. V. alginolyticus collagenase was added to a hyaluronan (HA)-based device to develop a novel debriding agent to improve the treatment of ulcers, necrotic burns, and decubitus in the initial phase of wound bed preparation. In this study, an in vitro biochemical characterisation of V. alginolyticus collagenase versus a commercial preparation from a Clostridium histolyticum strain on various dermal extracellular matrix (ECM) substrates was performed. V. alginolyticus collagenase demonstrated its ability to carry out the enzymatic cleavage of the substrate, allowing a selective removal of necrotic tissues while sparing healthy tissue, as reported in clinical studies and through routine clinical experience. in vitro tests under physiological conditions (pH, presence of Ca++, etc.) have demonstrated that V. alginolyticus collagenase exhibits very poor/limited non-specific proteolytic activity, whereas the collagenase preparation from C. histolyticum is highly active both on collagen and on non-collagenic substrates. This finding implies that while the V. alginolyticus enzyme is fully active on the collagen filaments that anchor the necrotic tissue to the wound bed, it does not degrade other minor, but structurally important, components of the dermal ECM. This feature could explain why collagenase preparation from V. alginolyticus has been reported to be much gentler on perilesional, healthy skin.


Assuntos
Colagenases/química , Colagenases/uso terapêutico , Colagenase Microbiana/química , Colagenase Microbiana/uso terapêutico , Especificidade por Substrato/efeitos dos fármacos , Cicatrização/efeitos dos fármacos , Ferimentos e Lesões/tratamento farmacológico , Clostridium histolyticum/química , Humanos , Vibrio alginolyticus/química
2.
Drugs ; 76(16): 1523-1528, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27770352

RESUMO

The introduction of collagenase Clostridium histolyticum (CCH) as a treatment option for Peyronie's disease (PD), defined as the abnormal formation of collagen on the tunica albuginea of the penis, has provided patients with a promising new conservative therapy. Studies have shown that CCH improves curvature by an average of 17°, and although patient and sexual partner satisfaction is high, the improvement has arguable clinical implications. Similarly, the efficacy and cost of CCH contrasts strongly with more invasive surgical management, and is further limited by rare, but serious, complications and several contraindications. The future of CCH involves well-designed trials analyzing the effects of CCH on patients who are currently not indicated for therapy, and the optimal amount of treatment for the most efficient treatment possible. CCH provides a promising treatment option for patients who do not desire invasive management, but need further trials to fully elucidate its treatment implications.


Assuntos
Clostridium histolyticum/química , Colagenase Microbiana/administração & dosagem , Induração Peniana/tratamento farmacológico , Humanos , Masculino , Colagenase Microbiana/química , Resultado do Tratamento
3.
PLoS One ; 10(5): e0124398, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25973613

RESUMO

Collagenase is an important enzyme which plays an important role in degradation of collagen in wound healing, cancer metastasis and even in embryonic development. However, the mechanism of this degradation has not yet been completely understood. In the field of biomedical and protein engineering, the design and development of new peptide based materials is of main concern. In the present work an attempt has been made to study the effect of DAla in collagen like peptide (imino-poor region of type I collagen) on the structure and stability of peptide against enzyme hydrolysis. Effect of replacement of DAla in the collagen like peptide has been studied using circular dichroic spectroscopy (CD). Our findings suggest that, DAla substitution leads to conformational changes in the secondary structure and favours the formation of polyproline II conformation than its L-counterpart in the imino-poor region of collagen like peptides. Change in the chirality of alanine at the cleavage site of collagenase in the imino-poor region inhibits collagenolytic activity. This may find application in design of peptides and peptidomimics for enzyme-substrate interaction, specifically with reference to collagen and other extra cellular matrix proteins.


Assuntos
Alanina/química , Colágeno Tipo I/química , Colagenase Microbiana/química , Peptídeos/química , Engenharia de Proteínas , Sequência de Aminoácidos , Clostridium histolyticum/química , Clostridium histolyticum/enzimologia , Colágeno Tipo I/síntese química , Hidrólise , Colagenase Microbiana/antagonistas & inibidores , Colagenase Microbiana/isolamento & purificação , Dados de Sequência Molecular , Peptídeos/síntese química , Estabilidade Proteica , Estrutura Secundária de Proteína , Estereoisomerismo
4.
J Bacteriol ; 195(2): 318-27, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23144249

RESUMO

Clostridium histolyticum secretes collagenases, ColG and ColH, that cause extensive tissue destruction in myonecrosis. The C-terminal collagen-binding domain (CBD) of collagenase is required for insoluble collagen fibril binding and subsequent collagenolysis. The high-resolution crystal structures of ColG-CBD (s3b) and ColH-CBD (s3) are reported in this paper. The new X-ray structure of s3 was solved at 2.0-Å resolution (R = 17.4%; R(free) = 23.3%), while the resolution of the previously determined s3b was extended to 1.4 Å (R = 17.9%; R(free) = 21.0%). Despite sharing only 30% sequence identity, the molecules resemble one another closely (root mean square deviation [RMSD] C(α) = 1.5 Å). All but one residue, whose side chain chelates with Ca(2+), are conserved. The dual Ca(2+) binding site in s3 is completed by an unconserved aspartate. Differential scanning calorimetric measurements showed that s3 gains thermal stability, comparable to s3b, by binding to Ca(2+) (holo T(m) = 94.1°C; apo T(m) = 70.2°C). holo s3 is also stabilized against chemical denaturants urea and guanidine HCl. The three most critical residues for collagen interaction in s3b are conserved in s3. The general shape of the binding pocket is retained by altered loop structures and side chain positions. Small-angle X-ray scattering data revealed that s3 also binds asymmetrically to minicollagen. Besides the calcium-binding sites and the collagen-binding pocket, architecturally important hydrophobic residues and the hydrogen-bonding network around the cis-peptide bond are well conserved within the metallopeptidase subfamily M9B. CBDs were previously shown to bind to the extracellular matrix of various tissues. Compactness and extreme stability in physiological Ca(2+) concentration possibly make both CBDs suitable for targeted growth factor delivery.


Assuntos
Clostridium histolyticum/química , Colagenases/química , Cálcio/metabolismo , Varredura Diferencial de Calorimetria , Cátions Bivalentes/metabolismo , Clostridium histolyticum/metabolismo , Colagenases/metabolismo , Cristalografia por Raios X , Guanidina/metabolismo , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Estabilidade Proteica , Espalhamento a Baixo Ângulo , Homologia de Sequência de Aminoácidos , Temperatura , Ureia/metabolismo
5.
Biol Chem ; 392(11): 1039-45, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21871007

RESUMO

Bacterial collagenases exhibit a multimodular domain organization. While the N-terminal collagenase unit harbors the catalytic zinc and suffices to degrade peptidic substrates, collagen substrates come in different types, explaining the requirement for accessory domains such as polycystic kidney disease (PKD)-like domains for efficient catalysis. How the recognition and unfolding of (micro-)fibrillar or triple-helical collagen is accomplished are only poorly understood. Here, we present the crystal structure of the PKD-like domain of collagenase G from Clostridium histolyticum. The ß-barrel structure reveals a two-tier architecture, connected by kinked hinge segments. Together with sheet extension as a generic oligomerization mechanism, this explains the cooperativity among accessory domains as well as their adaptivity to varying substrates.


Assuntos
Clostridium histolyticum/enzimologia , Colágeno/metabolismo , Colagenases/química , Colagenases/metabolismo , Sequência de Aminoácidos , Clostridium histolyticum/química , Cristalografia por Raios X , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína
6.
FEMS Immunol Med Microbiol ; 46(3): 360-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16553808

RESUMO

Clostridium histolyticum vacuolating cytotoxin was partially purified from culture broth using ammonium sulfate precipitation, gel filtration and hydrophobic interaction chromatography. The toxin caused vacuolization of HeLa cells visible under a light microscope after 2 h and distinct after 8 h. Transmission electron microscopy revealed the presence of numerous vacuoles, condensation of the mitochondrial matrix, increased cytoplasm density and increased amounts of heterochromatin. Apoptosis was not detected either by electron microscopy or by an apoptosis/necrosis discrimination assay with fluorescein-labeled annexin V and propidium iodide, or DNA fragmentation assay. Calcium ion influx was detected by flow cytometry after labeling cells with Fluo-4 AM. Vacuolation of HeLa cells by C. histolyticum cytotoxin was inhibited by bafilomycin A1, suggesting involvement of H+ -ATPase in the formation of vacuoles.


Assuntos
Clostridium histolyticum/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Vacúolos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Cálcio/metabolismo , Infecções por Clostridium/microbiologia , Clostridium histolyticum/fisiologia , DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Citometria de Fluxo , Células HeLa , Humanos , Marcação In Situ das Extremidades Cortadas , Macrolídeos/farmacologia , Microscopia Eletrônica de Transmissão , Vermelho Neutro/farmacocinética , Sódio/metabolismo , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores , ATPases Vacuolares Próton-Translocadoras/metabolismo , Vacúolos/microbiologia , Vacúolos/fisiologia
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