16S rDNA sequence analysis of culturable marine biofilm forming bacteria from a ship's hull

Marine bacteria from the hull of a ship in the form of biofilms or microfouling were isolated, cultured, and identified by phylogenetic analysis using 16S rDNA sequences. With an average length of 946 bp, all the 16 sequences were classified using the Ribosomal database project (RDP) and were submitted to the National Center for Biotechnology Information. Phylogenetic analysis using 16S rDNA sequences indicated that the 16 strains belonged to the Firmicutes (IK-MB6 Exiguobacterium aurantiacum, IK-MB7 Exiguobacterium arabatum, IK-MB8 Exiguobacterium arabatum, IK-MB9 Jeotgalibacillus alimentarius, IK-MB10 Bacillus megaterium, IK-MB11 Bacillus pumilus, IK-MB12 Bacillus pumilus, IK-MB13 Bacillus pumilus, IK-MB14 Bacillus megaterium), High GC, Gram-positive bacteria (IK-MB2 Micrococcus luteus, IK-MB5 Micrococcus luteus, IK-MB16 Arthrobacter mysorens), G-Proteobacteria (IK-MB3 Halomonas aquamarina, IK-MB15 Halotalea alkalilenta), CFB group bacteria (IK-MB1 Myroides odoratimimus), and Enterobacteria (IK-MB4 Proteus mirabilis). Among the 16 strains, representatives of the Firmicutes were dominant (56.25%) compared to the high GC, Gram-positive bacteria (18.75%), G-Proteobacteria (12.5%), CFB group bacteria (6.25%), and Enterobacteria (6.25%). Analysis revealed that majority of marine species found in marine biofilm are of anthropogenic origin.     

Antibiotic resistance patterns of coagulase-negative staphylococcus strains isolated from blood cultures of septicemic patients in Turkey

The aim of this study is to determine antibiotic resistance patterns and slime production characteristics of coagulase-negative Staphylococci (CoNS) caused nosocomial bacteremia. A total of 200 CoNS strains were isolated from blood samples of patients with true bacteremia who were hospitalized in intensive care units and in other departments of Istanbul University Cerrahpasa Medical Hospital between 1999 and 2006. Among 200 CoNS isolates, Staphylococcus epidermidis was the most prevalent species (87) followed by Staphylococcus haemolyticus (23), Staphylococcus hominis (19), Staphylococcus lugdunensis (18), Staphylococcus capitis (15), Staphylococcus xylosus (10), Staphylococcus warneri (8), Staphylococcus saprophyticus (5), Staphylococcus lentus (5), Staphylococcus simulans (4), Staphylococcus chromogenes (3), Staphylococcus cohnii (1), Staphylococcus schleiferi (1), and Staphylococcus auricularis (1). Resistance to methicillin was detected in 67.5% of CoNS isolates. Methicillin-resistant CoNS strains were determined to be more resistant to antibiotics than methicillin-susceptible CoNS strains. Resistance rates of methicillin-resistant and methicillin-susceptible CoNS strains to the antibacterial agents, respectively, were as follows: gentamicin 90% and 17%, erythromycin 80% and 37%, clindamycin 72% and 18%, trimethoprim-sulfamethoxazole 68% and 38%, ciprofloxacin 67% and 23%, tetracycline 60% and 45%, chloramphenicol 56% and 13% and fusidic acid 25% and 15%. None of the strains were resistant to vancomycin and teicoplanin. Slime production was detected in 86 of 200 CoNS strains. Resistance to methicillin was found in 81% of slime-positive and in 57% of slime-negative strains. Our results indicated that there is a high level of resistance to widely used agents in causative methicillin-resistant CoNS strains. However fusidic acid has the smallest resistance ratio, with the exception of glycopeptides. Additionally, most S. epidermidis strains were slime-positive, with statistically significant (p<0.001) association between methicillin resistance and slime production.     

Exiguobacterium himgiriensis sp. nov. a novel member of the genus Exiguobacterium, isolated from the Indian Himalayas

The taxonomic position of an orange coloured bacterium, strain K22–26^T isolated from a soil sample was studied using a polyphasic approach. The organism had phenotypic and chemotaxonomic properties consistent with its allocation into the genus Exiguobacterium. Phylogenetic analysis of the 16S rRNA gene sequence showed that strain K22–26^T belongs to the genus Exiguobacterium and was related to Exiguobacterium aurantiacum DSM 6208^T (99.0 %) Exiguobacterium mexicanum DSM 16483^T (98.6 %), Exiguobacterium aquaticum (98.6 %), Exiguobacterium aestuarii DSM 16306^T (98.1 %), Exiguobacterium profundum DSM 17289^T (98.1 %) and Exiguobacterium marinum DSM 16483^T (97.9 %), whereas sequence similarity values with respect to other Exiguobacterium species with validly published names were between 92.5–94.0 %. The major polar lipids detected were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. The major menaquinone was determined to be MK-7 (83 %) whereas MK-8 (11 %) and MK-6 (6 %) occur in smaller amounts. The peptidoglycan of the strain was found to contain l-lysine as the diagnostic diamino acid. The major fatty acids detected were iso C_13:0 (11.2 %), anteiso C_13:0 (15.4 %), iso C_15:0 (13.2 %) and iso C_17:0 (16.1 %). However, analysis of the DNA–DNA relatedness confirmed that strain K22–26^T belongs to a novel species. The G + C content of the strain K22–26^T was determined to be 50.1 mol %. The novel strain was distinguished from closely related type species of the genus Exiguobacterium using DNA–DNA relatedness and phenotypic data. Based on these differences, the strain K22–26^T should be classified as a novel species of the genus Exiguobacterium, for which the name Exiguobacterium himgiriensis sp. nov. strain K22–26^T (= MTCC 7628^T = JCM 14260^T) is proposed.     

Screening ofExiguobacterium acetylicum from soil samples showing enantioselective and alkalotolerant esterase activity

About 3,000 bacterial colonies with esterase activities were isolated from soil samples by enrichment culture and halo-size on Luria broth-tributyrin (LT) plates. The colonies were assayed for esterase activity in microtiter plates using enantiomerically pure (R)- and (S)-2-phenylbutyric acid resorufin ester (2PB-O-res) as substrates. Two enantioselective strains (JH2 and JH13) were selected by the ratio of initial rate of hydrolysis of enantiomerically pure (R)- and (S)-2-PB-O-res. When cell pellets were used, both strains showed hgh apparent enantioselectivity (E _app>100) for (R)-2PB-O-res and were identified asExiguobacterium acetylicum. The JH13 strain showed high esterase activity onp-nitrophenyl acetate (pNPA), but showed low lipase activity onp-nitrophenyl palmitate (pNPP). The esterase was located in the soluble fraction of the cell extract. The crude intracellular enzyme preparation was stable at a pH range from 6.0 to 11.0.     

Aureonitols A and B,Two New C13‐Polyketides from Chaetomium globosum,an Endophytic Fungus in Salvia miltiorrhiza

Two new C₁₃‐polyketides, aureonitols A and B ( 1 and 2 ), along with five known compounds ( 3 – 7 ), were isolated from the solid fermentation culture of the plant endophytic fungus Chaetomium globosum from the aerial parts of Salvia miltiorrhiza. The structures and absolute configurations of 1 and 2 were determined by comprehensive spectroscopic data analysis and computed methods. Compound 5 was found to display the remarkable antimicrobial activities against four multidrug‐resistant bacteria (Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, and Staphylococcus epidermidis) with MIC values of 3.13–6.25 μg/mL (ciprofloxacin: 0.78–1.56 μg/mL), and also against all tested fungal strains with MIC values of 3.13–25 μg/mL (ketoconazole: 0.78–12.50 μg/mL).     

Antimicrobial resistance and species identification of staphylococci isolated from the meat of wild rabbits (<Emphasis Type="Italic">Oryctolagus cuniculus</Emphasis>) in Slovakia

In 2009, a total of 113 strains of staphylococci were isolated from the thigh muscles of ten hunted and 20 farmed wild rabbits (Oryctolagus cuniculus) in the Slovak Republic. Only two isolates (1.8%) possessed coagulase activity, the rest of 111 staphylococcal isolates were coagulase-negative. Among them, six isolates (5.4%) showed the production of DNase. In each isolate, resistance to eight antibiotics by means of agar dilution test was tested. Based on these results, 110 isolates were found to be resistant to at least one antibiotic. Only one isolate was susceptible to all eight antibiotics tested. Another two isolates were susceptible, however, they showed intermediate susceptibility to cefoxitin. Resistance to ampicillin (78.8%), erythromycin (58.4%), penicillin (51.3%) and oxacillin (46.0%) was found most frequently. Twenty-six isolates (23.0%) were resistant to novobiocin. On the other hand, resistance to cefoxitin (8.0%) and gentamicin (1.8%) were quite rare. Fifteen percent of isolates were resistant to one antibiotic, simultaneous resistance to two, three, four and five antibiotics was confirmed in 22.1%, 23.9%, 21.2% and 13.3% of isolates, respectively. Except for two coagulase-positive Staphylococcus aureus isolates (1.8%), seven species of coagulase-negative staphylococci were identified using the MALDI BioTyper (TM) sytem as follows: Staphylococcus warneri (45.1%), Staphylococcus epidermidis (21.2%), Staphylococcus pasteuri (13.3%), Staphylococcus xylosus (8.0%), Staphylococcus capitis (7.1%), Staphylococcus haemolyticus (1.8%) and Staphylococcus cohnii ssp cohnii (1.8%).     

New Metabolites Produced by Cylindrocarpon sp. SY‐39 from a Driftwood

Four novel compounds, cylindropyrone A ( 1 ), 10′‐hydroxyilicicolinic acid D ( 3 ), cylindrolactones A ( 4 ) and B ( 5 ), together with known dihydroinfectopyrone ( 2 ) were isolated from the culture of Cylindrocarpon sp. SY‐39 from a driftwood. Their structures were elucidated using 1D‐ and 2D‐NMR spectroscopy. Compound 3 showed antimicrobial activity against Staphylococcus aureus with MIC value of 5.0 μg/mL.     

An On-Demand Metalloprotease from Psychro-Tolerant Exiguobacterium undae Su-1, the Activity and Stability of Which Are Controlled by the Ca2+ Concentration

We reported an on-demand type of metalloprotease from Exiguobacterium undae Su-1. Although this species of bacterium is known to inhabit the permafrost, there are no reports on either strong proteases or peptidases. We found that Su-1 protease is superior to commercially available proteases in proteolytic activity in a lower to normal range of temperature (10–50 °C) as well as in rapid inactivation heat-dependently on the Ca²⁺ concentration. These characteristics meet well with the demands from food processing and manufacturing. Biochemical investigations of the purified enzyme and protein structural analysis after gene cloning confirmed that Su-1 protease conserved high identity in its primary sequence with thermophilic proteases of the M4 family. On the other hand, its flexibility was enhanced when one Ca²⁺ binding site was lost and by replacement for proline and isoleucine residues.     

Molecular detection of enterotoxins E, G, H and I in Staphylococcus aureus and coagulase-negative staphylococci isolated from clinical samples of newborns in Brazil

Aims: The objective of this study was to investigate the detection of SEE, SEG, SEH and SEI in strains of Staphylococcus aureus and coagulase‐negative staphylococci (CNS) using RT‐PCR. Methods and Results: In this study, 90 Staph. aureus strains and 90 CNS strains were analysed by PCR for the detection of genes encoding staphylococcal enterotoxins (SE) E, G, H and I. One or more genes were detected in 54 (60%) Staph. aureus isolates and in 29 (32·2%) CNS isolates. Staphylococcus epidermidis was the most frequently isolated CNS species (n = 64, 71·1%), followed by Staphylococcus warneri (n = 8, 8·9%) and other species (Staphylococcus haemolyticus, Staphylococcus hominis, Staphylococcus lugdunensis, Staphylococcus simulans, Staphylococcus saprophyticus and Staphylococcus xylosus: n = 18, 20%). The genes studied were detected in Staph. epidermidis, Staph. warneri, Staph. haemolyticus, Staph. hominis, Staph. simulans and Staph. lugdunensis. The highest frequency of genes was observed in Staph. epidermidis and Staph. warneri, a finding indicating differences in the pathogenic potential between CNS species and highlighting the importance of the correct identification of these micro‐organisms. RT‐PCR used for the detection of mRNA revealed the expression of SEG, SEH and/or SEI in 32 (59·3%) of the 90 Staph. aureus isolates, whereas expression of some of these genes was observed in 10 (34·5%) of the 90 CNS isolates. Conclusions: Staphylococcus epidermidis was the most toxigenic CNS species. Among the other species, only Staph. warneri and Staph. lugdunensis presented a positive RT‐PCR result. PCR was efficient in confirming the toxigenic capacity of Staph. aureus and CNS. Significance and Impact of the Study: This study permitted to confirm the toxigenic capacity of CNS to better characterize the pathogenic potential of this group of micro‐organisms. In addition, it permitted the detection of SEG, SEH and SEI, enterotoxins that cannot be detected by commercially available immunological methods.     

Some bivalent metal complexes of Schiff bases containing N and S donor atoms

Schiff bases have been synthesized by the reaction of p-nitrobenzaldehyde, o-nitrobenzaldehyde and p-toluyaldehyde with 4-amino-5-mercapto-1,2,4-triazole. The ligands react with Co(II), Ni(II) and Zn(II) metals to yield (1:1) and (1:2) [metal:ligand] complexes. Elemental analyses, IR, ¹H NMR, electronic spectral data, magnetic susceptibility measurements, molar conductivity measurements and thermal studies have investigated the structure of the ligands and their metal complexes. The electronic spectral data suggests octahedral geometry for Co(II), Ni(II) and Zn(II). The antibacterial activities of the ligands and their metal complexes have been screened in vitro against three Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis and Bacillus subtilis) and two Gram-negative (Salmonella typhi and Pseudomonas aeruginosa) organisms. The coordination of the metal ion had a pronounced effect on the microbial activities of the ligands and the metal complexes have higher antimicrobial effect than the free ligands.     

Antimicrobial,spectral, magnetic and thermal studies of Cu(II), Ni(II), Co(II), UO2(VI) and Fe(III) complexes of the Schiff base derived from oxalylhydrazide

The Schiff base ligand, oxalic bis[(2-hydroxybenzylidene)hydrazide], H₂L, and its Cu(II), Ni(II), Co(II), UO₂(VI) and Fe(III) complexes were prepared and tested as antibacterial agents. The Schiff base acts as a dibasic tetra- or hexadentate ligand with metal cations in molar ratio 1:1 or 2:1 (M:L) to yield either mono- or binuclear complexes, respectively. The ligand and its metal complexes were characterized by elemental analyses, IR, ¹H NMR, Mass, and UV-Visible spectra and the magnetic moments and electrical conductance of the complexes were also determined. For binuclear complexes, the magnetic moments are quite low compared to the calculated value for two metal ions complexes and this shows antiferromagnetic interactions between the two adjacent metal ions. The ligand and its metal complexes were tested against a Gram + ve bacteria (Staphylococcus aureus), a Gram -ve bacteria (Escherichia coli), and a fungi (Candida albicans). The tested compounds exhibited high antibacterial activities.     

Conidiogenones H and I, two new diterpenes of Cyclopiane class from a marine-derived endophytic fungus Penicillium chrysogenum QEN-24S

Two new tetracyclic diterpenes of the rarely reported cyclopiane class, conidiogenones H and I ( 1 and 2 , resp.), along with five related congeners, conidiogenones B – D and F ( 3 – 5 and 6 , resp.) and conidiogenol ( 7 ), were characterized from the culture extracts of Penicillium chrysogenum QEN‐24S, an endophytic fungus derived from an unidentified marine red algal species of the genus Laurencia. The structures of these compounds were established on the basis of extensive spectroscopic analysis. The inhibitory activity of theses diterpenes against four bacteria and one pathogen fungus was evaluated. Conidiogenone B ( 3 ) showed potent activity against Methicillin resistant Staphylococcus aureus (MRSA), Pseudomonas fluorescens, P. aeruginosa, and Staphylococcus epidermidis (each with a MIC value of 8 μg/ml), while conidiogenol ( 7 ) showed obvious activity against P. fluorescens and S. epidermidis (each with a MIC value of 16 μg/ml). This is the first report on antimicrobial activity of cyclopiane diterpenes.     

白花地胆草的抗菌活性成分研究

从白花地胆草(Elephantopus tomentosus Linn.)全草的乙醇提取物中分离得到9个化合物,通过波谱分析,鉴定其结构分别为:表木栓醇(1)、羽扇豆醇(2)、6-deoxyisojacreubin(3)、桦木酸(4)、熊果酸(5)、阿魏酸(6)、3-甲酰吲哚(7)、半夏酸(8)和30-醛基羽扇豆醇(9)。所有化合物均为首次从白花地胆草中分离得到。用滤纸片琼脂扩散法测定上述化合物的抗菌活性,结果表明,化合物6和7对金黄色葡萄球菌的生长有抑制作用,化合物6和8对烟草青枯病菌的生长有抑制作用。     

Microbiological survey for selected bacterial pathogens in European storm petrel (<Emphasis Type="Italic">Hydrobates pelagicus</Emphasis>, Linnaeus 1758) from Grosa Island (Murcia,Southeastern Spain)

The current work shows the first step in the knowledge on the health status of European storm petrel (Hydrobates pelagicus) colony inhabiting Grosa Island (Murcia, SE Spain). We performed a screening about the bacterial pathogens carried by them (among the infectious agents checked, bacteria of the orders Mollicutes and Chlamydiales, and the genera Salmonella are of main interest) and compare these results with similar works performed in Larus species because most of the breeding colonies of storm petrel share habitats with gull colonies, and these could become pathogen reservoirs to petrels. Our results show the European storm petrels sampled have absence of pathogens of main interest and low levels of opportunistic pathogens. No Mycoplasma species were isolated, and no Chlamydophila psittaci were demonstrated by lipopolysaccharide antigen immunodetection. The commensal bacteria were isolated in higher frequencies than the previous [Staphylococcus epidermidis (5/15), Staphylococcus hominis (2/15) and Staphylococcus aureus (1/15)]. The rate of isolation of Gram-negative was lower than in the previous Gram-positive bacteria [Pasteurella sp. (1/15) and Pseudomonas aeruginosa (1/15)], and no Enterobacteriaceae were isolated. The absence of pathogen carriers on European storm petrel is the main conclusion of this survey; it is an evidence that the bacterial infectious pathogens described in gulls may not be an important selective force on their survival.     

A New Cytotoxic Carbazole Alkaloid and Two New Other Alkaloids from Clausena excavata

One new carbazole alkaloid, excavatine A ( 1 ), and two additional new alkaloids, excavatine B ( 2 ) and excavatine C ( 3 ), were isolated from the stems and leaves of Clausena excavata Burm .f. (Rutaceae). Their structures were determined on the basis of detailed spectroscopic analyses, especially 2D‐NMR and HR‐EI‐MS data. Compounds 1 – 3 were tested for their cytotoxic activities against A549, HeLa, and BGC‐823 cancer cell lines, and for their antimicrobial activities against Candida albicans and Staphylococcus aureus. Only 1 exhibited cytotoxicity against A549 and HeLa cell lines with the IC₅₀ values of 5.25 and 1.91 μg/ml, respectively.     

Expression of the guanosine-inosine kinase gene from Exiguobacterium acetylicum in Corynebacterium ammoniagenes and phosphorylation of inosine to produce inosine 5′-monophosphate

The guanosine-inosine kinase gene (gsk) isolated from Exiguobacterium acetylicum was expressed in an ATP-regenerating strain, Corynebacterium ammoniagenes. In order to induce its expression, three promoters (those for the Escherichia coli tac, Escherichia coli trp, and Corynebacterium glutamicum odhA gene) with the corresponding ribosome-binding sequences were examined. The E. coli trp promoter was most efficient with regard to inducing the expression of gsk in C. ammoniagenes. Further, the resulting strain, which has both inosine kinase activity and ATP-regenerating activity, was used to induce the phosphorylation of inosine to produce inosine 5′-monophosphate (5′-IMP), which is widely used as a flavor enhancer; approximately 80 g of 5′-IMP/l was produced with a molar conversion ratio of 80%.     

Campesterol Semi-Synthetic Derivatives as Potential Antibacterial: in vitro and in silico Evaluation

In this study, twelve campesterol derivatives ( 2 – 13 ) were prepared by esterification reaction at the hydroxy group in C-3 and catalytic hydrogenation at the carbon-carbon double bond in C-5(6). All obtained compounds were characterized by IR, ¹H-NMR, ¹³C-NMR, and MS spectra. Campesterol ( 1 ) and its derivatives ( 2 – 13 ) were evaluated in vitro against Staphylococcus aureus (ATCC 6538), Streptococcus mutans (ATCC 0046), Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), and Klebsiella pneumoniae (ATCC 10031) using the microdilution method. Among tested compounds, 4 , 6 , 9 , 11 , 12 , and 13 displayed the best antibacterial activity. Moreover, to support the antibacterial activity experiments, the investigation of molecular interactions of more active compounds, and also compound 1 and neomycin, used as starting material and positive control, respectively, at the binding site of the target proteins was performed using molecular docking simulations. Four compounds ( 7 , 9 , 10 and 11 ) are herein described for the first time.     

ent-Herqueidiketal and epi-Peniciherqueinone Isolated from a Mushroom Derived Fungus Penicillium herquei YNJ-35

A new polyaromatic metabolite, ent-herqueidiketal ( 1 ), and a new phenalenone derivative, epi-peniciherqueinone ( 2 ), along with twelve known compounds 3 – 14 , were isolated from the fungus Penicillium herquei YNJ-35, a symbiotic fungus of Pulveroboletus brunneopunctatus collected from Nangunhe Nature Reserve, Yunnan Province, China. The structures of 1 – 14 and the absolute configurations of 1 and 2 were determined by their spectroscopic data or by their single-crystal X-ray diffraction analysis or optical rotation values. Compound 1 showed strong antibacterial activity against Staphylococcus aureus (ATCC 29213) with minimum inhibitory concentration (MIC) of 8 μg/mL. In the cytotoxicity assays, compound 1 showed weak inhibitory activity against breast cancer MCF-7 and mice microglial BV2 cells with half maximal inhibitory concentration (IC₅₀) of 17.58 and 29.56 μM; compound 14 showed stronger cytotoxicity against BV2 and MCF-7 cells with IC₅₀ values of 6.57 and 10.26 μM.     

Cultivable Bacterial Diversity of Alkaline Lonar Lake, India

Aerobic, alkaliphilic bacteria were isolated and characterized from water and sediment samples collected in the winter season, January 2002 from alkaline Lonar lake, India, having pH 10.5. The total number of microorganisms in the sediment and water samples was found to be 10²–10⁶ cfu g⁻¹ and 10²–10⁴ cfu ml⁻¹, respectively. One hundred and ninety-six strains were isolated using different enrichment media. To study the bacterial diversity of Lonar lake and to select the bacterial strains for further characterization, screening was done on the basis of pH and salt tolerance of the isolates. Sixty-four isolates were subjected to phenotypic, biochemical characterization and 16S rRNA sequencing. Out of 64, 31 bacterial isolates were selected on the basis of their enzyme profile and further subjected to phylogenetic analysis. Phylogenetic analysis indicated that most of the Lonar lake isolates were related to the phylum Firmicutes, containing Low G+C, Gram-positive bacteria, with different genera: Bacillus, Paenibacillus, Alkalibacillus, Exiguobacterium, Planococcus, Enterococcus and Vagococcus. Seven strains constituted a Gram-negative bacterial group, with different genera: Halomonas, Stenotrophomonas and Providencia affiliated to γ-Proteobacteria, Alcaligenes to β-Proteobacteria and Paracoccus to α-Proteobacteria. Only five isolates were High G+C, Gram-positive bacteria associated with phylum Actinobacteria, with various genera: Cellulosimicrobium, Dietzia, Arthrobacter and Micrococcus. Despite the alkaline pH of the Lonar lake, most of the strains were alkalitolerant and only two strains were obligate alkaliphilic. Most of the isolates produced biotechnologically important enzymes at alkaline pH, while only two isolates (ARI 351 and ARI 341) showed the presence of polyhydroxyalkcanoate (PHA) and exopolysaccharide (EPS), respectively.     

MALDI-TOF Mass Spectrometry: A Powerful Tool for Clinical Microbiology at H?pital Principal de Dakar,Senegal (West Africa)

Our team in Europe has developed the routine clinical laboratory identification of microorganisms by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). To evaluate the utility of MALDI-TOF MS in tropical Africa in collaboration with local teams, we installed an apparatus in the Hôpital Principal de Dakar (Senegal), performed routine identification of isolates, and confirmed or completed their identification in France. In the case of discordance or a lack of identification, molecular biology was performed. Overall, 153/191 (80.1%) and 174/191 (91.1%) isolates yielded an accurate and concordant identification for the species and genus, respectively, with the 2 different MALDI-TOF MSs in Dakar and Marseille. The 10 most common bacteria, representing 94.2% of all bacteria routinely identified in the laboratory in Dakar (Escherichia coli, Klebsiella pneumoniae, Streptococcus agalactiae, Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus haemolyticus, Enterobacter cloacae, Enterococcus faecalis, and Staphylococcus epidermidis) were accurately identified with the MALDI-TOF MS in Dakar. The most frequent misidentification in Dakar was at the species level for Achromobacter xylosoxidans, which was inaccurately identified as Achromobacter denitrificans, and the bacteria absent from the database, such as Exiguobacterium aurientacum or Kytococcus schroeteri, could not be identified. A few difficulties were observed with MALDI-TOF MS for Bacillus sp. or oral streptococci. 16S rRNA sequencing identified a novel bacterium, “Necropsobacter massiliensis.” The robust identification of microorganisms by MALDI-TOF MS in Dakar and Marseille demonstrates that MALDI-TOF MS can be used as a first-line tool in clinical microbiology laboratories in tropical countries.