Peter Giesbrecht's research while affiliated with Robert Koch Institut and other places
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Publications (63)
X-ray diffraction, density measurements, and stereochemical data were used in order to disclose the architecture of murein, the rigid component of almost all bacterial cell walls. Dry densities of 1.38–1.39 g/cm3 were observed for Micrococcus luteus and Staphylococcus aureus. The X-ray data for gram-positive (S. aureus, M. luteus) and gram-negative...
The primary goal of this review is to provide a compilation of the complex architectural features of staphylococcal cell walls and of some of their unusual morphogenetic traits including the utilization of murosomes and two different mechanisms of cell separation. Knowledge of these electron microscopic findings may serve as a prerequisite for a be...
Electron microscopy studies revealed two different mechanisms of cell separation in Staphylococcus aureus. Both mechanisms were initiated by the centrifugal lytic action (directed outward from the center) of murosomes, which perforated the peripheral cell wall. Thereafter, during the first type of cell separation, murosomes also lysed large parts o...
In log-phase cells of staphylococci, cultivated under high, “non-lytic” concentrations of penicillin G, there occurred a novel killing process hitherto hidden behind seemingly bacteriostatic effects. Two events are essential for the apprearance of this “hidden death”: (i) the failure of the dividing cell to deposit enough fibrillar cross-wall mater...
In log-phase cells of staphylococci, cultivated under high, "non-lytic" concentrations of penicillin G, there occurred a novel killing process hitherto hidden behind seemingly bacteriostatic effects. Two events are essential for the appearance of this "hidden death": (i) the failure of the dividing cell to deposit enough fibrillar cross-wall materi...
In the early years of microbiological research, scientists coined the term “bacteriolysis” to describe the loss of turbidity of a bacterial culture. Viewing such a population under a microscope revealed that most or even all of the bacteria had disappeared. Today, the definition of bacteriolysis is basically still the same. It is understood as the...
Electron microscopic research into the murosomes of staphylococci has shown that the number of murosomes involved in penicillin-induced death varies depending on the experimental conditions employed. With 0.1 micrograms of penicillin G per ml, only 1 of a total of about 20 murosomes, the "killing murosome," completely perforated the pressure-stabil...
The addition of cationic proteins such as lysozyme, ribonuclease and cytochrome C enhanced the beta-lactam-induced bacteriolysis of staphylococci measured as release of wall label or by optical density. The treatment of staphylococci with penicillin plus cytochrome C resulted in a reduced viability of bacteria compared with those treated with penic...
L-[4,5-3H]isoleucine was introduced to label anteiso-fatty acid (AIFA)-containing lipids in Staphylococcus aureus SG 511. After an overnight incubation in peptone broth in the presence of 37 kBq L-[4,5-3H]isoleucine/ml, 8.5-13% of the total radioactivity applied was found to be incorporated into the cells. 22.4-25.6% of the incorporated radioactivi...
The anionic polyelectrolytes suramin and Evans Blue inhibited different autolytic systems involved in wall growth and wall turnover of growing staphylococci and in wall autolysis of resting bacteria. Moreover, both substances lowered the β-lactam-induced pre-lytic release of cytoplasmic constituents from staphylococci, and inhibited the β-lactam-in...
Clindamycin treatment of Staphylococcus aureus caused a remarkable thickening of the bacterial cell wall and made the bacterial wall much more resistant against lytic enzymes within bone marrow-derived macrophages as revealed by electron microscopy and radiolabeling experiments. This reduced wall degradability resulted from an increased number of O...
Synchronously growing staphylococci were treated with "lytic" concentrations of penicillin at different stages of their division cycle. Coulter Counter measurements and light microscopy were used to determine the onset of bacteriolysis. Independent of the stage of the division cycle at which penicillin was added, (i) the cells were always able to p...
Flow microcalorimetry in combination with photometric mass determination of staphylococci in suspension was used to reveal alterations in the intensity, extent and efficiency of bacterial metabolism during inhibition of protein synthesis by chloramphenicol. It could be demonstrated that these three parameters of metabolic activity were distinctly a...
By using the X-ray and infrared spectroscopic characteristics of various synthetic analogues and partial structures of lipid A in the dried state, a comparison of these compounds with their natural counterparts was undertaken. As judged by their X-ray diffraction and infrared spectroscopic features, the compounds tested could be divided into two ma...
The cellular immune system is known to be not capable of degrading the cell wall of certain pathogenic bacteria such as streptococci and staphylococci [5, 6, 15, 16].
We found that the three high molecular weight penicillin-binding proteins (PBP) 1, 2, and 3 of Staphylococcus aureus could be blocked by the β-lactam antibiotics imipenem, cefotaxime, and mecillinam, respectively. The inhibition of any of these PBPs was not sufficient for an antibacterial effect. Even the simultaneous blocking of PBPs 2 and 3, prev...
A novel, spectroscopic approach to the differentiation and identification of pathogenic bacteria was elaborated. The method essentially takes advantage of the Fourier transform infrared spectra of intact microorganisms. Such bacterial ir-spectra could be recorded within minutes with ample sensitivity and excellent reproducibility when applying a hi...
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Heparinoids and related negatively-charged substances caused suppression of the penicillin-induced bacteriolysis of staphylococci and a higher viability rate. Furthermore, the penicillin-induced release of cell wall material was reduced by these substances. The main reason for this suppression of bacteriolysis was an inhibition of the activity of c...
Bacteriostatic concentrations of trimethoprim, which possibly acts as a DNA-inhibitor, induced the swelling of staphylococci
and affected their cell walls, their cytoplasmic membrane and part of their autolytic wall system. Trimethoprim proved to
be the first growth-inhibiting drug that did not induce the formation of thickened cell walls in staphy...
Für die Induktion chronisch-entzündlicher Prozesse vom Typ der Arthritiden scheint die Tatsache von besonderer Bedeutung zu sein, daß abbauresistente und daher im Gewebe persistierende Antigene einen perpetuierenden Entzündungsmechanismus in Gang halten können (Kalden, 1984). Bei denjenigen chronisch-entzündlichen Prozessen, die nicht auf dem Vorha...
Liquoid (polyanethole sulfonate) was neither capable of influencing the growth nor the viability of staphylococci. But liquoid induced a suppression of the activity of different autolytic wall systems of normally growing staphylococci, i.e., autolysins which participate in cross wall separation as well as autolysins which are responsible for cell w...
In contrast to what has been postulated, penicillin G at its optimal lytic concentration of 0.1 microgram per ml did not lead to a detectable activation of autolytic wall processes in staphylococci in terms of the release of uniformly labelled wall fragments from cells pretreated with the drug for 1 h. Rather a considerable inhibition of this relea...
The actual reason for the penicillin-induced bacteriolysis of staphylococci was shown to be the “punching” of one or a few minute holes into the peripheral cell wall at predictable sites. These perforations were the result of the lytic activity of novel, extraplasmatic vesicular structures, located exclusively within the bacterial wall material, wh...
The conformational properties of the isolated S form of Salmonella sp. lipopolysaccharide (LPS), of Re mutant LPS, and of free lipid A were investigated by using X-ray diffraction and conformational energy calculations. The data obtained showed that LPS in a dried, in a hydrated, and probably also in an aqueous dispersion state is capable of formin...
The interaction of leucocytes with Staphylococcus aureus results in killing of the bacterial cells, but large portions of the bacterial cell walls persist apparently phagocytic cells for long periods. The mechanisms of biodegradation of staphylococci by leucocyte factors have shown that degradation of cell walls in vitro may be the result of the ac...
In spite of several attempts to introduce modern physical methods for the detection and identification of pathogenic bacteria, most routine identifications are presently based on microscopic, biochemical, and physiologic methods. Some emphasis has been put on the development for ready-to-use commercially available test kits, for example for the dif...
The invasions of tissues by pathogenic microorganisms is followed by a sequence of events which culminate in phagocytosis and the intracellular killing of the ingested agents, by “professional” phagocytes [19]. It is also expected that the rich arsenal of hydrolases present in neutrophils and macrophages, including the muralytic enzyme lysozyme is...
Using the method of conformational energy calculations, favoured conformations of a pseudomurein sugar strand built up from beta 1,3-linked N-acetyl-D-glucosamine and N-acetyl-L-talosaminuronic acid were obtained. Such a completely beta 1,3-linked polysaccharide primary structure, although contrasting with the originally proposed alternating beta 1...
Study of the Zn2+-containing d-alanyl-d-alanine-cleaving carboxypeptidase of Streptomyces albus G by small-angle X-ray scattering in solution yielded the following molecular parameters: radius of gyration R= 1.82 ± 0.05 nm; largest diameter D= 5.9 ± 0.2 nm; relative molecular mass Mr= 17000 ± 2000; volume V ∼ 35 ± 2 nm3; degree of hydration: 0.25 ±...
The effectiveness of host defence against staphylococcal infections depends on the capability of phagocytes to degrade the bacterial cell walls. Treatment with bacteriostatic agents like chloramphenicol could cause problems since under these drugs staphylococcal walls will be substantially thickened. This study presents evidence that the additional...
The mechanisms involved in the activation of autolytic enzymes in Staphylococcus aureus, by leukocyte extracts, cationic proteins, phospholipase A2, amines, and membrane-damaging agents was studied in a resting cell system as well as by growing staphylococci. The bacteria were labeled with [14C]N-acetylglucosamine and were subjected to a variety of...
The mechanisms involved in the activation of autolytic enzymes inStaphylococcus aureus, by leukocyte extracts, cationic proteins, phospholipase A2, amines, and membrane-damaging agents was studied in a resting cell system as well as by growing staphylococci. The bacteria were labeled with [14C]N-acetylglucosamine and were subjected to a variety of...
Infrared spectroscopic measurements are used to obtain insights into the three-dimensional architecture of peptidoglycan (murein), the rigid component of almost all bacterial cell walls. The infrared spectra of various types of peptidoglycans (including all chemotypes and examples of the so called A and B groups) were compared to each other and to...
In contrast to former findings lysozyme was able to attack the cell walls of Staphylococcus aureus under acid conditions. However, experiments with 14C-labelled cell walls and ribonuclease indicated that, under these conditions, lysozyme acted less as an muralytic enzyme but more as an activator of pre-existing autolytic wall enzymes. Electron micr...
Several bacteria contain autolytic wall enzymes within and beneath their cell walls capable of attacking their own wall material [23].
In order to compare possible conformations of murein and pseudomurein from Methanobacterium thermoautotrophicum with one another (especially with respect to the peptide moiety), X-ray diffraction data, density measurements, and conformational energy calculations were used. All results obtained indicated a similar certain layer-like arrangement and...
Cells exponentially grown from four strains ofS. aureus (SG 511, H, 52A5G, and248 PN-1) and uniformly labeled in their walls with3H-N-acetylglucosamine, were found to turn over their old walls at constant rates of up to 25% per generation. Wall turnover was not observed to follow first order kinetics, thus ruling out the implication that maintenanc...
Conformational energy calculations have been carried out on N-acetyl-L-alanyl-D-gamma-glutamyl-L-lysyl-D-alanyl-D-alanine as a model of the peptide moiety of peptidoglycan. Although many conformations were of comparable energy, particular favoured conformations were selected by assuming conformational similarity between the pentapeptide and the tet...
X-ray diffraction, density measurements, and stereochemical data were used in order to disclose the architecture of murein, the rigid component of almost all bacterial cell walls. Dry densities of 1.38–1.39 g/cm3 were observed for Micrococcus luteus and Staphylococcus aureus. The X-ray data for gram-positive (S. aureus, M. luteus) and gram-negative...
Recently the existence of crystal-like particle arrangements in the interlayer between cell wall and cytoplasmic membrane in Gram-positive bacteria could be demonstrated for the first time, Results so far show the crystal-like regions as networks of interlinked ring-shaped units.
For further analysis of these structures, despite the limited extensi...
By disintegration of the cell wall of staphylococci a definite interlayer located between the cytoplasmic membrane and the cell wall proper could be demonstrated for the first time (MW-interlayer). This MW-interlayer contains a sort of "cloddy" material in which clusters of embedded ring-like disks are hexagonally arranged in a crystal-like manner....
For several reasons, there is an increasing interest in studies concerning the morphogenesis of bacterial cell walls. Apparently, Escherichia coli is at the center of interest, but data on several gram-positive bacterial cell walls have also been published, and some excellent reviews on this subject exist. However, the morphogenesis of one of the m...
Cytoplasmic actomyosin fibrils of Physarum polycephalum were demonstrated by the freeze-etching technique. Within the fibrils the electron micrographs reveal 40-80 A thick filaments presumably representing F-actin. Thicker filaments (myosin) could not be detected. To avoid freezing artefacts, a pretreatment of the living material with 50% sucrose w...
The formation of characteristic clefts within the cell walls of staphylococci could be induced by small doses of penicillin. Beneath these clefts accumulations of filamentous cell wall precursors could be demonstrated. The clefts marked the transitional regions between old and new parts of the cell wall where, apparently, lytic cell wall enzymes ar...
Citations
... De-O-acetylation. O-Acetyl groups were removed with 0.05 N NaOH for 1 h at 37°C (15, 19), and the removal was verified by FT-IR spectroscopy (21). Phagocytosis. ...
... Since the ester bond of the 0-acetyl group is relatively weak, it is tempting to speculate that this site may be enzymatically altered in vivo to regulate SWS-promoting activity of MPs. However, 0-acetyl groups reduce the degradability of the bacterial cell walls by lysozyme (3,5,14), the best-characterized enzyme known to digest bacterial cell walls, and by intact polymorphonuclear leukocytes and macrophages (39). Furthermore, the degree of 0 acetylation is elevated when bacteria are allowed to enter the stationary phase of growth or when they are treated with certain bacteriostatic antibiotics (6,14,15,33). ...
... We could argue that, on one hand, PBPs of E. coli are enzymes that catalyze energy-independent reactions. On the other hand, crystallographic analysis of the peptidoglycan layer reveals that the peptide moieties of the peptidoglycan layer are located at both sides of the glycan chains (3). Those facing the OM might be properly oriented substrates for those PBP enzymes located outside the IM. ...
... This phenomenon could, however, be similar to the findings that spermine (a polyamine) protected the lysis of M. lysodeikticus by lysozyme presumably by stabilizing the protoplasts generated following the lysis of the murein (139A). Further support for the assumption that polyanions might regulate autolytic enzymes came from our studies on penicillin-induced lysis in staphylococci (118). It is thought that bacteriolytic concentrations of penicillin might lyse cells by releasing LTA, believed to be the regulator of autolysins in gram-positive bacteria (128,129). ...
... Interestingly, the degree of O-acetylation seems to be negatively affected by β-lactam antibiotics that target proteins that are related to transpeptidation reactions in the synthesis of peptidoglycans. O-acetylation of peptidoglycan appears to play a not-yet resolved role in the cross-linking reaction [79][80][81]. ...
... Certain bacteria, such as Streptococcus pyogenes and other gram-positive cocci, are killed extensively by penicillin in spite of the fact that they are not lysed by the antibiotic (6,14,25). Moreover, specific blockage of penicillin-induced lysis in Streptococcus pneumoniae and Staphylococcus aureus decreased drug-induced killing only marginally, thus suggesting that other, autolysis-independent pathways were involved in penicillin-induced lethality (11,13,26,31,36,37). Recently, a breakthrough study indicated that vancomycinand penicillin-tolerant pneumococci carried alterations in the two-component regulatory system VncS-VncR, which was not directly related to autolysis (31). ...
... mAU, milliabsorbance units. replicate by a distinctive program, whereby cell division planes are built perpendicular to previous planes (13) and bulk de novo peptidoglycan synthesis occurs at the cross-wall, the peptidoglycan layer that separates a mother cell into two daughters (47). S. aureus mutants lacking lytN display delayed growth as well as structural defects to the cell wall envelope in that the otherwise homogeneous appearance of peptidoglycan is per-turbed, giving rise to disordered layers of cell wall and irregular cell shapes. ...
... In contrast, peaks at 1374 cm −1 (C-H bend of methyl groups) and 1277.98 cm −1 (stretching of aromatic amines [C-N], stretching of alcohols [C-O], carboxylic acids, esters, and ethers) shifted to lower wavenumbers after the addition of As(III). Since the shifting peaks at 1750-1500 cm −1 and 1500-1200 cm −1 are associated with bacterial cell wall components such as proteins, peptides, and fatty acids, this could indicate that strain SEK2 cell wall functional groups are involved in arsenite binding (Naumann et al. 1991). With the addition of arsenite, new peaks of stretching of aromatics (C-C) at 1442.28 cm −1 , primary aromatic amines (C-N) at 1323.17 cm −1 , and phosphates (P = O) at 1246.80 cm −1 were observed. ...
... Recently, we attempted to differentiate Pseudomonas spp., and some similar soil isolates by an improved technique of Fourier-transform IR spectroscopy (Filip and Herrmann, 2001). This method, i.e., FT-IR spectroscopy, has been successfully used by other authors too, who attempted identification of different clinically relevant bacteria (Giesbrecht et al., 1985; Holt et al., 1995; Choo-Smith et al., 2001). The aim of our present study was to obtain spectroscopic fingerprints from differently cultivated B. subtilis as it could gain some importance for rapid detection and identification of this bacterium. ...
... The impressively increased degradation resistance after pretreatment with clindamycin may be ascribed to an increased O-acetyl substitution of the murein after clindamycin treatment. In earlier studies, it was demonstrated that treatment of S. aureus with antibiotics of a similar mode of action, such as chloramphenicol or erythromycin, increased the number of O-acetyl groups of the murein (4, 16, 31, 32) and the degradation resistance of their cell walls against lysozyme in vitro (14). The importance of O-acetyl groups of murein for the degradation resistance was also demonstrated with certain strains of Neisseria gonorrhoeae (24) showing a degradability by human polymorphonuclear leukocytes that was only one-fourth that of non-O-acetylated murein (25). ...
