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At least 19 recordsLinked to original sources
PubMed1983

Urinary recovery of N-formimidoyl thienamycin (MK0787) as affected by coadministration of N-formimidoyl thienamycin dehydropeptidase inhibitors.

N-Formimidoyl thienamycin (MK0787) undergoes renal metabolism by a dipeptidase, dehydropeptidase I, located on the brush border of the proximal tubular cells. The effects of two inhibitors (MK-789 and MK-791) of dehydropeptidase I on the pharmacokinetics of N-formimidoyl thienamycin were studied in 41 healthy subjects receiving various combinations of N-formimidoyl thienamycin and MK-789 or MK-791. Both inhibitors affected the plasma kinetics of N-formimidoyl thienamycin only to a small extent. Plasma concentrations and the area under the plasma concentration curve increased about 20% with a proportional decrease in plasma clearance. Plasma half-life was not altered significantly. Coadministration of MK-789 or MK-791 resulted in uniform and marked increases in urinary recovery and renal clearance of N-formimidoyl thienamycin. Thus, at an N-formimidoyl thienamycin/MK-791 ratio of 1:0.25 or higher, the urinary recovery was about 72% in all subjects, whereas it varied between 7.7 and 43% when N-formimidoyl thienamycin was given alone. The ratio of the N-formimidoyl thienamycin and MK-791 doses affected response. At relatively higher doses of MK-791, significant increases of N-formimidoyl thienamycin urinary recovery, renal clearance, and urine concentrations occurred during the later part of the 10-h observation period after each administration. At a 1:1 ratio of the two drugs, the inhibition of renal metabolism of N-formimidoyl thienamycin was maintained for at least 8 h, whereas renal clearance declined as soon as 4 h after the administration of a 1:0.25 ratio. The results indicated that MK-789 and MK-791 alter the renal excretion of N-formimidoyl thienamycin from glomerular filtration plus tubular secretion to glomerular filtration only, possibly by competitively inhibiting the penetration of N-formimidoyl thienamycin into the proximal tubular cells.

Adult↗
PubMed1980

In vitro activity of N-formimidoyl thienamycin (MK0787), a crystalline derivative of thienamycin.

N-Formimidoyl thienamycin (MK0787) is a derivative of thienamycin, a unique, new beta-lactam antibiotic. Its activity against 285 aerobic and facultatively anaerobic clinical isolates was compared with the activities of cephalothin, ampicillin, penicillin G, ticarcillin, and tobramycin. All of the 285 isolates, with the exception of 1 Staphylococcus epidermidis isolate, were inhibited by a concentration of N-formimidoyl thienamycin of less than or equal to 8 micrograms/ml. More than 50% of all isolates were inhibited by the lowest concentration of N-formimidoyl thienamycin tested (0.125 micrograms/ml); 98% of Staphylococcus aureus and 80% of S. epidermidis isolates were inhibited by N-formimidoyl thienamycin at a concentration of 0.125 micrograms/ml. Only 2 of 45 enterococci were not inhibited by 1 microgram of N-formimidoyl thienamycin per ml, and this drug was the most active agent tested against 162 gram-negative bacilli. It inhibited more than 95% of the gram-negative isolates at a concentration of less than or equal to 2 micrograms/ml. N-Formimidoyl thienamycin was as active or more active than tobramycin against Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis and substantially more active than ticarcillin. All 16 isolates of Klebsiella pneumoniae were inhibited by less than or equal to 0.5 micrograms of N-formimidoyl thienamycin per ml. The marked in vitro activity of this drug against a wide variety of clinical isolates makes it a promising new antibiotic.

Anti-Bacterial Agents↗
PubMed1980

Antibacterial activities of a new stabilized thienamycin, N-formimidoyl thienamycin, in comparison with other antibiotics.

The in vitro activity of a new crystalline derivative of thienamycin, N-formimidoyl thienamycin (MK0787), was tested against 46 laboratory reference strains and 2,158 clinical isolates of gram-positive and -negative bacteria, including anaerobes, and compared with cefoxitin, cefaxolin, carbenicillin, and amikacin. MK0787 was significantly more active than the reference antibiotics against most bacteria tests. MK0787 was 16- to 500-fold more active than the other antibiotics against Staphylococcus aureus, Streptococcus pneumoniae, and group A and group B streptococci, inhibiting most isolates at concentrations less than 0.031 micrograms/ml. The inhibition concentration against over 90% of 156 strains of Streptococcus faecalis was 1 micrograms/ml. MK0787 had slightly less activity than carbenicillin against Haemophilus influenzae. The minimal inhibitory concentrations of MK0787 against strains of Enterobacter spp., Citrobacter spp., Serratia marcescems. Pseudomonas aeruginosa, and Clostridium difficile that are resistant to currently available antibiotics were less than or equal to 4 micrograms/ml. The only species found resistant to MK0787 was Pseudomonas maltophilia, which was equally nonsusceptible to the other reference antibiotics.

Anti-Bacterial Agents↗
PubMed1982

A comparison of the antibacterial activities of N-formimidoyl thienamycin (MK0787) with those of other recently developed beta-lactam derivatives.

The antibacterial activity of N-formimidoyl thienamycin (MK0787) was evaluated in 335 clinical isolates of ampicillin-resistant Enterobacteriaceae, 50 Pseudomonas aeruginosa strains, 28 Acinetobacter spp., 50 Streptococcus faecalis strains, and 7 oxacillin-resistant Staphylococcus aureus strains and was compared with the recently developed beta-lactam antibiotics mezlocillin, cefuroxime, cefazedone, cefoperazone, cefotaxime, and moxalactam. Among the gram-negative bacteria, N-formimidoyl thienamycin was less active than cefotaxime against Klebsiella, Serratia, and Proteus spp. but had comparable activity against Escherichia coli and Enterobacter strains. Activity of the thienamycin derivative was somewhat lower than that of moxalactam against most of the strains and superior to that of mezlocillin, cefuroxime, and cefoperazone. Moreover, N-formimidoyl thienamycin was the most active drug against P. aeruginosa and Acinetobacter spp. and had activity comparable to that of ampicillin against Streptococcus faecalis. N-Formimidoyl thienamycin was bactericidal at concentrations less than twice the minimal inhibitory concentration (MIC) in all gram-negative isolates tested. Oxacillin-resistant staphylococci (MIC of oxacillin, greater than 4 micrograms/ml) were inhibited at low concentrations of the thienamycin derivative (90% MIC, 0.25 micrograms/ml); however, N-formimidoyl thienamycin was not bactericidal at the 90% MIC. The antibacterial activity of N-formimidoyl thienamycin against all of the gram-negative bacilli was observed to be independent of beta-lactamase production.

Acinetobacter↗
PubMed1983

Pharmacokinetics and tolerance of N-formimidoyl thienamycin (MK0787) in humans.

The pharmacokinetics of intravenously administered N-formimidoyl thienamycin (MK0787) were studied in 14 healthy male subjects in a single-dose study, in which the volunteers received N-formimidoyl thienamycin with and without probenecid, and in a multiple-dose study, in which the subjects were given 250 or 500 mg every 8 h for 10 doses. High dose-related plasma concentrations of N-formimidoyl thienamycin were achieved; co-administration with probenecid resulted in only minor increases in these concentrations. No accumulation in plasma was seen after multiple doses. The plasma half-life of N-formimidoyl thienamycin was slightly less than 1 h and did not increase significantly with the coadministration of probenecid. The urinary recovery of N-formimidoyl thienamycin varied between 6.0 and 38.4% of the dose with a marked intersubject variability. Variations in individual subjects were small, however, when the urinary recoveries after repeated doses were compared. These results were in agreement with previous animal studies showing a renal metabolism of N-formimidoyl thienamycin. Probenecid administration resulted in a marked decrease in N-formimidoyl thienamycin urinary recovery. In vitro experiments showed that the decay of N-formimidoyl thienamycin in spiked pretreatment urine samples was 2 to 5%/h with more rapid degradation at acidic than at basic pH.

Adult↗
PubMed1981

In vitro activity of N-formimidoyl thienamycin, moxalactam, and other new beta-lactam agents against Bacteroides fragilis: contribution of beta-lactamase to resistance.

N-Formimidoyl thienamycin (N-F-thienamycin) and moxalactam were compared with other currently available and investigational antibiotics against 100 clinical isolates of Bacteroides fragilis by an agar dilution method. N-F-thienamycin was the most active among the beta-lactam agents tested, with a minimal inhibitory concentration for 90% of isolates (MIC90) of 0.25 micrograms/ml. Moxalactam was next in activity, with an MIC90 of 4 micrograms/ml. N-F-thienamycin was somewhat more active, and moxalactam was slightly less active, than metronidazole and clindamycin. An increase in inoculum size caused an increase in the MIC of N-F-thienamycin, cefoperazone, and cefotaxime. This inoculum effect could influence the usefulness of these drugs in certain clinical conditions. The minimal bactericidal concentration was less than two times the MIC for most agents and less than four times the MIC for all beta-lactam agents at each inoculum size tested. Investigation of the mechanism of resistance to beta-lactam agents demonstrated a correlation between the level of resistance and beta-lactamase activity in each strain tested. N-F-thienamycin and cefoxitin were not hydrolyzed, and moxalactam was less susceptible to hydrolysis than the other beta-lactam antibiotics. Moxalactam and N-F-thienamycin may prove to be useful against infections with B. fragilis.

Anti-Bacterial Agents↗
PubMed1983

[Effect of multiresistance on the minimal inhibitory concentration of N-formimidoyl thienamycin and 6 comparing substances against P. aeruginosa and 4 Enterobacteriaceae species].

The minimal inhibitory concentrations (MICs) of multiresistant strains of P. aeruginosa and four species of Enterobacteriaceae were compared with those of more sensitive ones in N-f-thienamycin and six other antibiotics. The greatest difference between these two differently resistant bacterial populations was found in cefoperazone and the beta-lactamase-instable piperacillin. The latter was used for comparison purposes. The activity of cefsulodin was distinctly reduced in multiresistant strains of P. aeruginosa. Cefotaxime and lamoxactam displayed slightly elevated MICs in multiresistant strains. In N-f-thienamycin a significant difference between the multiresistant and the more sensitive population could not be verified (p greater than 0.05). In this regard it resembles fosfomycin. beta-lactam antibiotics could be ranked by means of correlation analysis of their MICs. Using piperacillin as a reference antibiotic the following order of succession could be arranged according to correlation coefficients in P. aeruginosa: cefoperazone, cefsulodin, lamoxactam, cefotaxime and N-f-thienamycin. For the Enterobacteriaceae species some antibiotics could not be evaluated in this test. Moreover, it was recognized that there was an obvious correlation between the activities of lamoxactam and cefotaxime in P. aeruginosa (r = 0.81) and E. coli (r = 0.80). A correlation was also observed between those of cefsulodin and cefoperazone in P. aeruginosa (r = 0.75). Lower correlation coefficients were seen in N-f-thienamycin with cefoperazone, piperacillin and cefsulodin in P. aeruginosa and with cefoperazone in Klebsiella spec.. Notwithstanding, strains resistant to cefsulodin and cefoperazone were inhibited by concentrations less than or equal to 8 micrograms/ml of N-f-thienamycin. These results showed that in N-f-thienamycin, cefotaxime and lamoxactam multiresistance has only a minimal influence on the MICs of the species of Enterobacteriaceae examined. For therapeutic considerations concerning multiresistance the small differences recognized among these three antibiotics might be without significance. However, N-f-thienamycin was distinctly more active in multiresistant strains of P. aeruginosa than the other beta-lactam antibiotics tested.

Anti-Bacterial Agents↗
PubMed1980

Influence of inoculum size on activity of cefoperazone, cefotaxime, moxalactam, piperacillin, and N-formimidoyl thienamycin (MK0787) against Pseudomonas aeruginosa.

Forty clinical isolates of Pseudomonas aeruginosa were tested for their susceptibility to cefoperazone, cefotaxime, moxalactam, piperacillin, N-formimidoyl thienamycin (MK0787), and gentamicin at three different inocula. At an inoculum of 5 x 10(3) colony-forming units (CFU) per ml, the minimum inhibitory concentrations (in micrograms per milliliter) for 90% of isolates (MIC90) were as follows: gentamicin, 1; N-formimidoyl thienamycin, 2; cefoperazone, 4; piperacillin, 8; moxalactam, 16; and cefotaxime, 16. When the inoculum was increased to 5 x 10(5) CFU/ml, the MIC90 for all drugs tested increased. Among the beta-lactam antibiotics, N-formimidoyl thienamycin and cefoperazone had the lowest MIC90 (8 micrograms/ml) at this inoculum. When the inoculum was increased further to 5 x 10(7) CFU/ml, an MIC90 could be determined only for gentamicin and N-formimidoyl thienamycin (4 and 8 micrograms/ml, respectively). Indeed, the MIC50 for moxalactam, cefotaxime, cefoperazone, and piperacillin was 128 micrograms/ml or more at this inoculum. The minimum bactericidal concentration for 90% of isolates (MBC90) at an inoculum of 5 x 10(5) CFU/ml ranged from 8 micrograms/ml for gentamicin and N-formimidoyl thienamycin to 128 micrograms/ml for cefotaxime. At the highest inoculum, however, whereas the MBC90 for gentamicin and N-formimidoyl thienamycin remained at 8 micrograms/ml, the MBC90 for each of the other drugs was greater than 128 micrograms/ml. N-Formimidoyl thienamycin was the only drug tested for which an MIC100 and MBC100 (MIC and MBC for 100% of isolates) could be determined, and these were not significantly different from the MIC90 and MCB90.

Anti-Bacterial Agents↗
PubMedDate not supplied

The in vitro activity of N-formimidoyl thienamycin compared with other broad-spectrum cephalosporins and with clindamycin and metronidazole.

N-formimidoyl thienamycin is a new semisynthetic beta-lactam antibiotic still awaiting clinical trials. We have investigated the in vitro activity of N-formimidoyl thienamycin against 413 fresh clinical isolates and compared it to other new beta-lactam drugs and to clindamycin and metronidazole in the agar dilution test. All coliforms were inhibited by less than or equal to 1 mg/l and no member of the Proteus group was resistant to more than 8 mg/l of N-formimidoyl thienamycin. The MICs for Pseudomonas aeruginosa were less than or equal to 4 mg/l. Beta-haemolytic streptococci, pneumococci and staphylococci, including methicillin-resistant strains, were all inhibited by 0.125 mg/l or less. Streptococcus faecalis strains were all susceptible to less than or equal to 2 mg/l. N-formimidoyl thienamycin was highly active against the anaerobes tested. N-formimidoyl thienamycin exhibited bactericidal activity, and changes in inoculum size had little effect on the MICs. This data has shown that N-formimidoyl thienamycin has excellent antibacterial activity and an unusually broad spectrum of activity.

Cephalosporins↗
PubMed1982

Lack of in vivo and in vitro bactericidal activity of N-formimidoyl thienamycin against enterococci.

The minimal bactericidal concentrations of N-formimidoyl thienamycin (N-f-thienamycin) against 21 strains of enterococci isolated from patients with infective endocarditis were determined by macro- and microdilution methods. By a macrodilution technique with the minimal bactericidal concentration defined as greater than or equal to 99.9% killing of an initial inoculum, all 21 strains of enterococci were found to have minimal bactericidal concentration/minimal inhibitory concentration ratios of greater than or equal to 32. The mean minimal inhibitory concentration was 1.5 micrograms/ml (range, 0.5 to 4 micrograms/ml), and the minimal bactericidal concentration was greater than or equal to 128 micrograms/ml. The disparity between the results of our study and those published elsewhere, which reported that N-f-thienamycin is bactericidal in vitro against enterococci, may represent the relative insensitivity of the microdilution method in determining greater than or equal to 99.9% killing. The lack of in vitro bactericidal activity of N-f-thienamycin against enterococci was confirmed in vivo in the rabbit model of experimental endocarditis. N-f-Thienamycin was no more effective than penicillin alone in the treatment of experimental enterococcal endocarditis and was less effective than the combination of penicillin and gentamicin. The results indicate that N-f-thienamycin should not be used alone in the treatment of enterococcal endocarditis.

Animals↗
PubMed1982

Susceptibility of Neisseria meningitidis and Neisseria gonorrhoeae isolates to N-formimidoyl thienamycin.

A diverse collection of 123 meningococcal and 126 gonococcal isolates was tested for susceptibility to N-formimidoyl thienamycin (N-F-thienamycin; MK0787) and to penicillin G (PEN). All of the meningococci were susceptible to both of these, as well as to rifampin. Among gonococci, beta-lactamase-producing strains, which were resistant to PEN, were susceptible to N-F-thienamycin. Among non-beta-lactamase-producing strains, the minimal inhibitory concentrations of N-F-thienamycin and PEN were less than or equal to 1.28 micrograms/ml. Of these, the strains with PEN minimal inhibitory concentrations toward the higher end of the range were likely to be more susceptible to N-F-thienamycin, whereas the strains that were highly susceptible to PEN were likely to have higher minimal inhibitory concentrations of N-F-thienamycin.

Anti-Bacterial Agents↗
PubMed1994

Mutants of Streptomyces cattleya defective in the synthesis of a factor required for thienamycin production.

Thienamycin non-producing mutants of Streptomydes cattleya were identified that displayed a cross-feeding relationship. A diffusible product from one of these mutants (RK-11) resulted in restoration of thienamycin production when fed to cultures of another mutant (RK-4). In vivo radiolabeling experiments were conducted to test whether the RK-11 mutant produced a late biosynthetic intermediate which contained a carbapenem ring and a cysteaminyl and/or a hydroxyethyl side chain. Both [35S]cystine and [methyl-3H]methionine were used to label the RK-11 product which was then fed to RK-4 cultures. None of the thienamycin subsequently produced by RK-4 converter cells was labeled, implying the lack of either side chain of the thienamycin molecule in the RK-11 product. Further stability studies suggested that the RK-11 product does not contain a carbapenem ring. Additional feeding experiments with RK-4 cells also ruled out the possibility that the RK-11 product is a co-factor necessary for thienamycin production. It is concluded that the RK-11 product may regulate expression of the thienamycin gene cluster.

Chromatography, High Pressure Liquid↗
PubMed1981

Comparative activity of N-formimidoyl thienamycin with third generation cephalosporins and ureido penicillins against multiple resistant Serratia marcescens.

Twenty multiple resistant clinical isolates were tested with N-formimidoyl thienamycin, moxalactam, cefotaxime, cefoperazone, and the three ureidopenicillins: azlocillin, mezlocillin, and piperacillin. A concentration of less than 0.97 microgram/ml inhibited 100% of organisms for N-f-thienamycin and cefotaxime, 90% for moxalactam, and 60% for cefoperazone. An increase in inoculum from 10(3) to 10(6) cells reduced activity fourfold for 95% of isolates with cefoperazone, 70% with N-formimidoyl thienamycin, 65% for cefotaxime, but only 15% for moxalactam. For ureidopenicillins, 85% of strains tested had MIC's less than or equal to 15.6 micrograms/ml. An inoculum effect was observed in only 35-50%. At 10(3), the cidal concentration was the same or twofold greater than the inhibitory level for N-f-thienamycin and cephalosporins in 70% of strains tested and 65% for penicillins. With 10(6), the 70% value remained for N-f-thienamycin but was reduced to 45% for cefotaxime and 25% for moxalactam; 85% demonstrated greater than eightfold differences with cefoperazone. Single step high-level resistance was observed to moxalactam (20%). Carbenicillin resistant strains were cross-resistant to the ureidopenicillins. N-f-thienamycin and cefotaxime appeared comparable, although important differences between morphological alteration and metabolism may influence their therapeutic effectiveness.

Azlocillin↗
PubMed1981

In vitro activity of N-formimidoyl thienamycin in comparison with cefotaxime, moxalactam, and ceftazidime.

The in vitro activity of N-formimidoyl thienamycin (N-f-thienamycin) was compared with the activities of other B-lactam antibiotics, using over 500 clinical bacterial isolates. N-f-Thienamycin inhibited 90% of the isolates of the common Enterobacteriaceae between 0.006 and 2 microgram/ml, regardless of their resistance to amoxicillin, ticarcillin, or cephalothin. It was, however, fourfold less active than moxalactam and ceftazidime and eightfold less active than cefotaxime. N-f-Thienamycin was nearly as active as ceftazidime against Pseudomonas aeruginosa (mean minimal inhibitory concentration, 3.0 microgram/ml) and eightfold more active than cefotaxime and moxalactam. In contrast to cefotaxime, moxalactam, and ceftazidime, N-f-thienamycin was highly active against enterococci (mean minimal inhibitory concentration, 1.3 microgram/ml) and staphylococci. The oxacillin-susceptible Staphylococcus aureus were inhibited between 0.03 and 0.12 microgram/ml, and the oxacillin-resistant S. aureus were inhibited between 0.12 and 2 microgram/ml. The high activity of N-f-thienamycin against both of the most important gram-positive and gram-negative organisms makes it a very promising new antibiotic.

Anti-Bacterial Agents↗
PubMed1982

In vitro activity of N-formimidoyl-thienamycin in comparison to that of moxalactam and cefotaxime against gentamicin-resistant gram-negative bacteria.

The inhibitory and bactericidal activity of N-formimidoyl-thienamycin in vitro against 131 clinical isolates selected for their gentamicin resistance was compared with that of cefotaxime and moxalactam. All strains were inhibited by N-formimidoyl-thienamycin concentrations within a range of 0.12-4 mg/l. N-formimidoyl-thienamycin was less active than cefotaxime and moxalactam against Escherichia coli and Klebsiella spp., and more active than all other antibiotics tested against Serratia spp., Enterobacter cloacae, Pseudomonas aeruginosa and Acinetobacter spp. In contrast to the other antibiotics N-formimidoyl-thienamycin showed a narrow margin of difference between minimal inhibitory and minimal bactericidal concentrations. N-formimidoyl-thienamycin is a promising antibiotic for the treatment of hospital infections with multi-resistant organisms.

Acinetobacter↗
PubMed2003

The biosynthetic gene cluster for the beta-lactam carbapenem thienamycin in Streptomyces cattleya.

beta-lactam ring formation in carbapenem and clavam biosynthesis proceeds through an alternative mechanism to the biosynthetic pathway of classic beta-lactam antibiotics. This involves the participation of a beta-lactam synthetase. Using available information from beta-lactam synthetases, we generated a probe for the isolation of the thienamycin cluster from Streptomyces cattleya. Genes homologous to carbapenem and clavulanic acid biosynthetic genes have been identified. They would participate in early steps of thienamycin biosynthesis leading to the formation of the beta-lactam ring. Other genes necessary for the biosynthesis of thienamycin have also been identified in the cluster (methyltransferases, cysteinyl transferases, oxidoreductases, hydroxylase, etc.) together with two regulatory genes, genes involved in exportation and/or resistance, and a quorum sensing system. Involvement of the cluster in thienamycin biosynthesis was demonstrated by insertional inactivation of several genes generating thienamycin nonproducing mutants.

Amino Acid Sequence↗
PubMed1981

Preparation and antibacterial activity of delta 1-thienamycin.

delta 1-Thienamycin (2), a double-bond isomer of thienamycin, was prepared by isomerizing N-[[(p-nitrobenzyl)oxy]-carbonyl]thienamycin p-nitrobenzyl ester (5b) with DBU in Me2SO followed by hydrogenolysis of the protecting groups. When evaluated in a disc-diffusion antibacterial assay, delta 1-thienamycin was found to be essentially devoid of activity. The lack of antibacterial activity was ascribed to a chemically less reactive beta-lactam amide bond than that found in thienamycin.

Bacteria↗
PubMed1983

N-formimidoyl thienamycin: in vitro comparison with cefoxitin and tobramycin against clinical, bacterial isolates.

The in vitro activity of the novel beta-lactam antibiotic, N-formimidoyl thienamycin (N-f thienamycin) has been compared with those of cefoxitin and tobramycin. An agar dilution method was employed. N-f thienamycin was active against all Enterobacteriaceae isolates (MIC less than or equal to 4 mg/l). All Pseudomonas aeruginosa isolates were inhibited by 2 mg/l. N-f thienamycin was also active against Acinetobacter calcoaceticus (96 per cent inhibited by 0.5 mg/l) and Gram-positive cocci. All enterococci were inhibited by 2 mg/l. The drug was active against Haemophilus influenzae (MIC less than or equal to 1 mg/l) and the Bacteroides fragilis group (MIC less than or equal to 0.5 mg/l). Cefoxitin was inactive against most Enterobacter and A. calcoaceticus isolates and all P. aeruginosa and enterococcal isolates. Tobramycin was virtually inactive against Gram-positive cocci other than Staphylococcus aureus. N-f thienamycin thus has a broad spectrum of in vitro activity, greater than that of cefoxitin and tobramycin, and may therefore be useful in the treatment of serious infection, particularly when the aetiology is unknown.

Acinetobacter↗