scholarly journals Evaluation of numerical analysis of SDS-PAGE of protein patterns for typingEnterobacter cloacae

1989 ◽  
Vol 103 (2) ◽  
pp. 265-274 ◽  
Author(s):  
M. Costas ◽  
L. L. Sloss ◽  
R. J. Owen ◽  
M. A. Gaston

SUMMARYTwenty cultures comprising 13 clinical isolates ofEnterobacter cloacaefrom two hospitals. the type and another reference stain ofE. cloacaeand the type strains of four otherEnterobactersp. and ofEscherichia coli, were characterized by one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDSPAGE) of whole-cell proteins. The protein patterns were highly reproducible and were used as the basis of a numerical analysis which divided the clinical isolates into nine clearly defined protein types. Comparison with established typing methods indicated that the discrimination of SDS-PAGE was similar to that achieved with conventional typing methods and all strain groups recognized by combined sero/phage typing were also found by SDS-PAGE. In addition, protein typing sub-divided a group of four serotype O3 isolates that were difficult to distinguish by phage typing. We conclude that high-resolution SDS-PAGE of proteins provides an effective method of typing isolates ofE. cloacae.

1990 ◽  
Vol 104 (3) ◽  
pp. 455-465 ◽  
Author(s):  
M. Costas ◽  
B. Holmes ◽  
L. L. Sloss

SUMMARYTwenty–four cultures comprising 20 clinical isolates of ‘Klebsiella aerogenes’ from two hospitals, a reference strain of ‘K. aerogenes’ and the type strains of three otherKlebsiellaspecies, were characterized by one–dimensional sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) of whole–cell proteins. The protein patterns were highly reproducible and were used as the basis of a numerical analysis which divided the clinical isolates into 12 protein types. Comparison with established typing methods indicated that the level of discrimination of SDS–PAGE was similar to that achieved with conventional typing methods but the strains were grouped differently. Protein typing sub–divided five serotype K3 isolates that could also be distinguished by phage typing. Conversely, three strains of protein type 11 were clearly distinguishable by both serotyping and phage typing. We conclude that high–resolution SDS–PAGE of proteins provides an effective adjunct to other methods for typing isolates of ‘K. aerogenes’.


1990 ◽  
Vol 105 (1) ◽  
pp. 107-117 ◽  
Author(s):  
B. Holmes ◽  
M. Costas ◽  
L. L. Sloss

SUMMARYTwenty-five cultures comprising 18 clinical isolates ofSerratia marcescensfrom two hospitals, the type strain ofS. marcescens, two reference strains ofS. marinorubra, the type or a reference strain of three other Serratia species and a reference strain of undetermined species, were characterized by one-dimensional sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) of whole-cell proteins. The protein patterns were highly reproducible and were used as the basis of a numerical analysis which divided the clinical isolates into eight protein types. Comparison with O-serotyping indicated that the level of discrimination by SDS–PAGE was similar. As with O-serotyping, a secondary scheme, such as phage typing, is necessary to differentiate strains of the same protein type. We conclude that high-resolution SDS–PAGE of proteins provides an effective adjunct to other methods for typing isolates ofS. marcescens.


1994 ◽  
Vol 113 (1) ◽  
pp. 1-12 ◽  
Author(s):  
M. Costas ◽  
B. Holmes ◽  
M. Ganner ◽  
S. L. W. On ◽  
P. N. Hoffman ◽  
...  

SUMMARYSeventy-three cultures ofClostridium difficileisolated both during, and in the period immediately following, an outbreak of infection in a group of three hospitals, were characterized by one-dimensional sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) of whole-cell proteins. Each protein pattern was characterized by the presence of one or two dense bands which were highly reproducible. The protein patterns were used as the basis for a numerical analysis which divided the strains into five phenons (electrophoretic or EP types). The majority, 60 of the 73 cultures, belonged to a single phenon which included strains from both patients and the environment. We conclude that high-resolution SDS–PAGE of proteins provides an effective method for typingC. difficileand therefore for tracing the possible spread of epidemic strains in hospitals and other institutions, thereby allowing a better understanding of the epidemiology of the organism.


1990 ◽  
Vol 105 (1) ◽  
pp. 127-137 ◽  
Author(s):  
M. Costas ◽  
B. Holmes ◽  
L. L. Sloss ◽  
S. Heard

SUMMARYForty-two cultures of pseudomonas comprising 28 clinical isolates from a pseudo-outbreak on a Special-Care Baby Unit and 14 reference strains, including 9 type strains, of variousPseudomonasspecies, were characterized by one-dimensional sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE) of whole-cell proteins. The protein patterns were highly reproducible and were used as the basis for a numerical analysis which divided the strains into 9 phenons. Two of the 28 clinical isolates were identified by biochemical tests asP. pickettiiand their identification was confirmed by SDS–PAGE as they fell in the same phenon as the type strain of the species. The remaining 26 isolates, which could not be identified on phenotypic tests, fell in the same phenon as three reference strains of ‘P. thomasii’. The protein patterns provided the first clear evidence thatP. pickettiiand ‘P. thomasii’ were separate taxa and that the ‘outbreak’ was polymicrobial in origin, in line with the probable aqueous source of contamination. We conclude that high-resolution SDS–PAGE of proteins provides an effective method of identifying and differentiating pseudomonads, especially where this cannot be done adequately using conventional biochemical tests.


2008 ◽  
Vol 71 (11) ◽  
pp. 2289-2294 ◽  
Author(s):  
MING-LUN CHIANG ◽  
WEI-LI HO ◽  
ROCH-CHUI YU ◽  
CHENG-CHUN CHOU

Cells of Vibrio parahaemolyticus 690 were subjected either to heat shock at 42°C for 45 min or to ethanol shock in the presence of 5% ethanol for 60 min. The protein profiles of the unstressed and stressed V. parahaemolyticus cells were compared. Additionally, the induction of DnaK- and GroEL-like proteins in the unstressed and stressed cells of V. parahaemolyticus was also examined. Analysis with one-dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) indicated that three proteins with molecular masses of 93, 77, and 58 kDa were induced by both heat shock and ethanol shock. The protein patterns revealed by two-dimensional electrophoresis were more detailed than those revealed by one-dimensional SDS-PAGE. It was found that heat shock and ethanol shock affected the expression of a total of 28 proteins. Among them, four proteins with molecular masses of 94, 32.1, 26.7, and 25.7 kDa were enhanced by both heat shock and ethanol shock. Furthermore, immunoblot analysis showed the presence of a GroEL-like protein with a molecular mass of 61 kDa in the test organism, with the heat-shocked and ethanol-shocked cells producing a GroEL-like protein in a larger quantity than the unstressed cells. However, DnaK-like protein was not detectable in either the unstressed or the stressed cells.


Author(s):  
Frederico Guilherme Coutinho Abath ◽  
Luís Carlos de Sousa Ferreira

In the present study three techniques for obtaining outer membrane enriched fractions from Yersinia pestis were evaluated. The techniques analysed were: differential solubilization of the cytoplasmic membrane with Sarkosyl or Triton X-100, and centrifugation in sucrose density gradients. The sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of outer membrane isolated by the different methods resulted in similar protein patterns. The measurement of NADH-dehydrogenase and succinate dehydrogenase (inner membrane enzymes) indicated that the outer membrane preparations obtained by the three methods were pure enough for analytical studies. In addition, preliminary evidences on the potential use of outer membrane proteins for the identification of geographic variants of Y. pestis wild isolates are presented.


Antibiotics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 39
Author(s):  
Salman Sahab Atshan ◽  
Rukman Awang Hamat ◽  
Marco J. L. Coolen ◽  
Gary Dykes ◽  
Zamberi Sekawi ◽  
...  

Staphylococcus aureus (S. aureus) infections are notoriously complicated by the ability of the organism to grow in biofilms and are difficult to eradicate with antimicrobial therapy. The purpose of the current study was to clarify the influence of sub-inhibitory concentrations (sub-MICs) of daptomycin and tigecycline antibiotics on biofilm adhesion factors and exoproteins expressions by S. aureus clinical isolates. Six clinical isolates representing positive biofilm S. aureus clones (3 methicillin-sensitive S. aureus (MSSA) and 3 methicillin-resistant S. aureus (MRSA)) were grown with sub-MICs (0.5 MIC) of two antibiotics (daptomycin and tigecycline) for 12 h of incubation. RNA extracted from culture pellets was used via relative quantitative real-time-PCR (qRT-PCR) to determine expression of specific adhesion (fnbA, fnbB, clfA, clfB, fib, ebps, cna, eno) and biofilm (icaADBC) genes. To examine the effect of sub-MIC of these antibiotics on the expression of extracellular proteins, samples from the culture supernatants of six isolates were collected after 12 h of treatment with or without tigecycline in order to profile protein production via 2D gel sodium dodecyl sulfate-polyacrylamide gel electrophoresis (2D gel-SDS-PAGE). Sub-MIC treatment of all clinical MRSA and MSSA strains with daptomycin or tigecycline dramatically induced or suppressed fnbA, fnbB, clfA, clfB, fib, ebps, cna, eno, and icaADBC gene expression. Furthermore, sub-MIC use of tigecycline significantly reduced the total number of separated protein spots across all the isolates, as well as decreasing production of certain individual proteins. Collectively, this study showed very different responses in terms of both gene expression and protein secretion across the various isolates. In addition, our results suggest that sub-MIC usage of daptomycin and tigecycline could signal virulence induction by S. aureus via the regulation of biofilm adhesion factor genes and exoproteins. If translating findings to the clinical treatment of S. aureus, the therapeutic regimen should be adapted depending on antibiotic, the virulence factor and strain type.


1996 ◽  
Vol 70 (3) ◽  
pp. 253-257 ◽  
Author(s):  
M. Siles-Lucas ◽  
C. Cuesta-Bandera

AbstractA comparison was made, by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), of excretory/secretory (ES) – crude and immunopurified (with the corresponding anti-host serum) hydatid fluids – and somatic (S) – protoscoleces – proteins, from several ovine, equine, swine, bovine and human Echinococcus granulosus Spanish isolates. Likewise, the host influence on parasitic ES protein expression was studied, comparing purified hydatid fluids from ovine and equine cysts obtained from natural hosts and in RNMI mice. Purified hydatid fluids patterns, under reducing conditions, yielded the most precise differentiation of Spanish strains of E. granulosus into three groups (ovine—bovine-human, equine and swine), the finding of a characteristic 82 kDa band in equine isolates, and an unusual arrangement of bands between 50 and 6 kDa in swine samples. In addition, differences were found amongst crude and purified hydatid fluids, especially in bovine and swine isolates. The total protein patterns of protoscoleces were most complex, and therefore could not be used for strain differentiation. Finally, the purified hydatid fluids from cysts developed in natural and experimental hosts showed similar protein patterns, suggesting the lack of host influence, under our experimental conditions, on the expression of parasitic ES proteins.


Sign in / Sign up

Export Citation Format

Share Document