• Korean Journal of Veterinary Research
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• v.38 no.4
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• pp.843-852
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• 1998

From Jan. 1996 to Oct. 1997, 29 pigs with 40-70 days old showing dyspnea inappetite and polyserositis were collected and carried out necropsy, bacterial culture, histopathology, avidin biotin complex(ABC) stain, fluorescent antibody(FA) test, and electron microscopy. In the study, 4 strains from 3 pigs were isolated from meninges, pleura and synovial fluid and also were identified as Haemophilus parasuis serovar 5. Main histopathological lesions of 29 pigs with polyserositis were frequently composed of fibrinous peritonitis(27), pleurisy(22), interstitial pneumonia(21), fibrinous epicarditis(20), fibrinopurulent meningitis(8) and synovitis(4). By ABC stain, 11/29(37.9%) pigs with polyserositis were confirmed to have H parasuis serovar 5 in the cytoplasm of macrophages and neutrophils in cerebral meninges, epicardium, pleura surface of lung or serosa of spleen. ABC stain(20.8~40.0%) to detect H parasuis serovar 5 in tissues was more sensitive than bacterial culture(10.3%), but less sensitive than FA test(62.5%) using frozen tissues even though the result of 8 cases. By electron microscopy, a bacterium was also detected in the cytoplasm of macrophages in purulent exudate of cerebral meninges. Consequently, we confirmed that H parasuis serovar 5 has been involving to cause pigs with polyserositis and can be detected by FA and ABC stain as reliable diagnostic tools.

• Pediatric Infection and Vaccine
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• v.27 no.1
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• pp.62-68
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• 2020

Acute bacterial sinusitis is one of the most common diseases in children, and 5-13% of patients with viral upper respiratory infection experience secondary bacterial sinusitis as a complication. Isolated sphenoid sinusitis is rarer than frontal, maxillary, and ethmoid sinusitis. However, it presents potentially devastating complications, such as cranial nerve involvement, brain abscess, and meningitis, owing to its anatomical location. Nontypeable Haemophilus influenzae (NTHi) commonly causes acute bacterial sinusitis but rarely causes bacteremia, particularly in immunocompetent patients. We present a rare case of a 14-year-old boy with bacteremia due to isolated sphenoid sinusitis caused by NTHi.

• The Journal of the Korean Society for Microbiology
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• v.20 no.1
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• pp.73-77
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• 1985

Haemophilus aphrophilus is a fastidious gram-negative bacillus found in mouth of normal individuals. Though H. aphrophilus infection is quite rate, it includes such serious ones as endocarditis and brain abscess. The authors isolated H. aphrophilus from five patients with the diagnosis of lung abscess, conjunctivitis, brain abscess and facial masticator space abscess. Two of the patients died. Three of the patients also yielded other species of bacteria from the same specimens. One of the isolate was intermediately susceptible to amikacin and resistant to tobramycin, indicating the necessity of a routine susceptibility test in order to select the proper antimicrobial agents. Since H. aphrophilus can be differentiated from other similar organisms by morphological and biochemical characteristics, one should determie the possibility of this organism when fastidious gram-negative bacilli are isolated from blood or from sites adjacent to upper respiratory tract.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.520-524
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• 2004

A protein that exhibited a high similarity to a major serine transporter of Escherichia coli, SdaC, was found in Haemophilus injluenzae Rd. Also, $Na^+$-stimulated serine transport activity was detected in the cells. The sdaC of H. injluenzae was cloned and the properties of the transporter were investigated. The activity of serine transport was stimulated by $Na^+$. Uptake of $Na^+$ elicited by L-serine influx into cells was also observed, which supports the idea that L-serine is transported by a mechanism of $Na^+$serine symport. No uptake of $H^+$ elicited by L-serine influx was detected. This result was not consistent with that obtained with the homologous protein, SdaC of E. coli, which uses $H^+$as a coupling cation. The serine transport via the SdaC of H. influenzae was not inhibited by other amino acids such as threonine or D-serine like the SdaC of E. coli. Thus, the SdaC of H. influenzae is a $Na^+$-dependent L-serine specific symporter and an unusual natural mutant. The $K_m$ and the $V_{max}$, value for the serine transport in the SdaC of H. influenzae were $7.6\mu$M and 22.9 nmol/min/mg protein, respectively.

• Journal of Microbiology and Biotechnology
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• v.19 no.12
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• pp.1582-1589
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• 2009

Bacterial UDP-N-acetylglucosamine enolpyruvyl transferase (MurA) catalyzes the transfer of enolpyruvate from phosphoenolpyruvate (PEP) to uridine diphospho-N-acetylglucosamine (UNAG), which is the first step of bacterial cell wall synthesis. We identified thimerosal, thiram, and ebselen as effective inhibitors of Haemophilus influenzae MurA by screening a chemical library that consisted of a wide range of bioactive compounds. When MurA was preincubated with these inhibitors, their 50% inhibitory concentrations ($IC_{50}s$) were found to range from 0.1 to $0.7\;{\mu}M$. In particular, thimerosal suppressed the growth of several different Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, and Salmonella typhimurium at a concentration range of $1-2\;{\mu}g/ml$. These inhibitors covalently modified the cysteine residue near the active site of MurA. This modification changed the open conformation of MurA to a more closed configuration, which may have prevented the necessary conformational change from occurring during the enzyme reaction.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1307-1309
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• 2012

Haemophilus parasuis causes contagious porcine Gl$\ddot{a}$sser's disease leading to severe losses in the swine industry. In this study, we established an efficient Escherichia coli-based system for the expression of H. parasuis major outer-membrane protein (MOMP) that has been known as a good vaccine candidate against Gl$\ddot{a}$sser's disease. Use of an E. coli-derived pelB leader sequence made it possible to produce recombinant MOMP (rMOMP) as the soluble forms without an additional refolding process. Using two different animal models, it was evaluated that the rMOMP was capable of inducing a significant immune response and providing protection against H. parasuis infection.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.575-578
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• 2000

The N-acetylneuraminate lyase(NALase) from Escherichia coli was cloned and it was compared to that from Haemophilus influenzae and Clostridium perfringens. NALase from E. coli was expressed in very high level(about 6U/mg). The ManNAc Km value of three enzymes was almost the same. Pyruvate inhibited from H. influenzae was inhibited by GlcNAc in lower level than the others. The crude extract has about 30 times more activity than the cell for the substrate and product diffusion limit problem. The pH stability of three enzymes at pH 11 was also checked for its importance in the direct synthesis of Neu5Ac from GlcNAc and pyruvate at high alkaline condition.

• Pediatric Infection and Vaccine
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• v.26 no.3
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• pp.188-193
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• 2019

Since the implementation of conjugate Haemophilus influenzae serotype b (Hib) vaccine, the rate of infections caused by Hib has dramatically decreased, and the proportion of infections caused by non-type b H. influenzae has increased. Cerebral venous sinus thrombosis (CVST) is rare; however, it should be considered as a potential complication of bacterial meningitis. Herein, we report about a child who developed CVST after being diagnosed with H. influenzae serotype f meningitis.

• Journal of Veterinary Clinics
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• v.3 no.1
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• pp.243-253
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• 1986

In recent years much attention has been paid to swine respiratory infection caused by Haemophilus(H.) Pleuropneumoniae with rapid expansion of pork industry in Korea. The organism may cause an acute respiratory infection with high morbidity and mortality, or it may also cause chronic persistent infection, resulting in loss of body weight. The present study was performed to observe the etiologic situation of H. Pleuropneumoniae infection by evaluating bacteriological, serological examinations with the lungs and sera collected from slaughtered pigs in Daegu city, respectively. In addition, antibiotic susceptibility test was carried out against the isolated strains of H. Pleuropneumoniae. The results obtained are summarized as follows : 1. Only 10 strains of H. Pleuropneumoniae were isolated from the 120 cases of swine lungs examined, and biological and biochemical characteristics of the isolates were identical with that of standard strains(serovar 1 to 6). 2. Out of 336 swine sera examined, 108(32.1%) were shown to be positive against H. Pleuropneumoniae by latex agglutination test. 3. Antibiotic susceptibility test revealed that 10 isolates of H. Pleuropneumoniae were sensitive to 16 kinds of antibiotic such as ampicillin, benzylpenicillin, piperacillin, cephalothin, cefazolin, cefamandol, cefoperagon, lactomoxycefa, tetracycline, minocycline, chloramphenicol, gentamicin, kanamycin, amikacin, colistin and nalidixic acid, whereas cloxacillin, erythromycin, kitasamycin, lincomycin, oleand-amycin, and bacitracin were resistent.

• Journal of Microbiology
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• v.41 no.2
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• pp.78-82
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• 2003

We identified two proteins in Haemophilus influenzae Rd that exhibited high similarity to two major serine transporters of Escherichia coli (SstT and SdaC). Then, we investigated serine transport in H. influenzae Rd and detected $Na^{+}$-stimulated L-serine transport activity. The optimum NaCl concentration for this stimulation was about 20 mM. The uptake of $Na^{+}$ by H. influenzae Rd was found to be elicited by L-serine influx, which supports the idea that L-serine is transported by a mechanism of $Na^{+}$/serine symport. No uptake of $H^{+}$ elicited by L-serine influx was detected. $Na^{+}$/serine symport activity was not inhibited by other amino acids such as L-threonine or D-serine. Two distinct Km values were obtained from the kinetic analysis of serine transport. Thus, two serine transport pathways may exist in H. influenzae Rd, and it appears that both systems are stimulated by $Na^{+}$.